The biggest change in this week’s MK5-MIL assessment is on the battlefield. Ukraine’s Operation Vivaldi has disrupted Russia’s northern approach toward the Donetsk Fortress Belt and shown that Ukrainian forces can still create local operational surprise after years of increasingly static warfare.

The second major shift is happening farther behind the lines. Ukrainian refinery strikes are now disrupting a substantial share of Russian diesel production, while Russia has found a way to sustain its missile campaign with converted training weapons as Ukraine’s Patriot interceptor supply becomes dangerously thin.

Russia’s confrontation with NATO is also becoming harder to separate from the war itself. European governments reported another series of drone incursions, border incidents, and hybrid threats this week, while Poland publicly warned that Moscow could deliberately stage attacks designed to look accidental.

What changed this week

Four indicators stand out.

Russian breakthrough risk: ↓ Lower

Ukraine’s Operation Vivaldi has damaged Russia’s attempt to approach Sloviansk and the wider Fortress Belt from the north.

Ukraine’s 3rd Army Corps says Ukrainian forces cleared or retook about 85 square kilometers north of Lyman. ISW assesses that Ukraine combined operational secrecy, intermediate-range strikes, counter-drone systems, and attacks on Russian electronic warfare and logistics to create local tactical maneuver.

Russia hasn’t abandoned the larger Donetsk campaign. Russian forces are moving armor and drone-support assets toward the Dobropillya direction, which could support renewed mechanized attacks from the south during the fall.

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Negotiation activity: → High, but stalled

The energy ceasefire discussed this week hasn’t become an operational agreement.

President Donald Trump said Russia and Ukraine had agreed to stop attacking each other’s energy infrastructure. Neither government subsequently confirmed a completed agreement, and both countries continued hitting energy targets.

Ukraine says it will stop its refinery campaign if Russia gives a credible reciprocal commitment. The Kremlin has welcomed the general idea but has attached additional demands involving sanctions and maritime exports.

Reuters (Reuters)

Ukrainian deep-strike pressure: ↑ Strongly rising

The refinery campaign has moved beyond isolated disruption.

Reuters reported this week that three of Russia’s six largest diesel-producing refineries had either sharply reduced production or stopped operating after drone attacks. Those six facilities normally account for roughly half of Russian diesel production.

The consequences are now feeding back into Western policy. Trump publicly called on Ukraine to stop attacking Russian diesel infrastructure as global diesel supplies tightened and U.S. prices climbed.

Reuters (Reuters)

Russian gray-zone pressure against NATO: ↑ Rising

NATO fighters shot down a drone over Lithuania this week, the first interception of its kind in Lithuanian airspace. Lithuania hasn’t established that Russia deliberately sent the drone across the border, and officials said an investigation was still underway.

Polish Prime Minister Donald Tusk went further on September 17. Tusk said intelligence available to Poland indicates Russia may deliberately launch drone or missile attacks against NATO countries and portray the incidents as accidents to complicate the alliance’s response.

France separately said September 18 that Russian hybrid activity against Europe has intensified and announced plans for stronger protection of critical infrastructure.

AP and Reuters (AP News)

Battlefield

The battlefield picture improved modestly for Ukraine this week.

Operation Vivaldi is the most important development. Ukrainian forces counterattacked the Russian salient north of Lyman after months of Russian efforts to position forces for a wider encirclement of Ukraine’s defensive belt around Sloviansk, Kramatorsk, Druzhkivka, and Kostyantynivka.

Ukrainian commander Andrii Biletskyi says the operation disrupted Russia’s planned northern pincer. ISW considers Ukraine’s performance significant because Ukrainian forces managed to restore limited tactical maneuver in an environment dominated by drones, mines, artillery, and persistent surveillance.

The method matters almost as much as the territory.

Ukraine attacked Russian fuel and logistics networks in occupied Luhansk, weakening electronic warfare systems that depend on diesel generators. Ukrainian forces simultaneously used counter-drone systems and operational secrecy to reduce Russian awareness of the developing counterattack.

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Russia still has options. Russian commanders are concentrating armored equipment around Dobropillya and may attempt mechanized attacks against the southern side of the Fortress Belt as fall weather changes battlefield conditions.

MIL therefore doesn’t interpret Operation Vivaldi as the beginning of a broad Ukrainian counteroffensive. The operation does weaken the case that Russia can convert persistent offensive pressure into an inevitable breakthrough.

Trend: ↑ Modest improvement for Ukraine

Confidence: High that Russia’s northern plan was disrupted; medium on how much operational freedom Ukraine can recover

Diplomacy

Diplomacy produced more activity than restraint this week.

Washington pushed for a moratorium on attacks against energy infrastructure after Ukrainian strikes damaged Russian refineries and global diesel prices climbed. Ukraine said it was prepared to participate if Russia genuinely stopped attacking Ukrainian energy targets.

The Kremlin called the proposal a good idea but also demanded protection for Russian maritime exports and relief from sanctions.

The battlefield response was immediate. Russia struck petrol stations and other infrastructure in Ukraine on September 15, while Ukraine attacked the Syzran refinery and Russian drone-production facilities.

Reuters (Reuters)

The episode strengthens a distinction MIL has been making for several weeks. Negotiation activity doesn’t necessarily indicate declining escalation.

Russia, Ukraine, and the United States can negotiate while both combatants simultaneously increase military and economic pressure. Bargaining and escalation are occurring together.

Current MIL probabilities

• Substantive negotiations within 1–2 months: 80–90% ↑
• Limited or sector-specific agreement: 35–45% ↑
• Broad ceasefire covering most combat: 15–25% →
• Durable political settlement: under 15% →

The probability of a limited agreement rises because Washington is now actively pushing a specific reciprocal arrangement involving energy targets. MIL doesn’t raise the broader ceasefire estimate because the territorial and security disputes remain unresolved.

Ukrainian deep strikes

Ukraine’s refinery campaign is becoming one of the strongest strategic pressure mechanisms available to Kyiv.

Reuters reported September 15 that half of Russia’s six largest diesel-producing refineries had substantially reduced output or shut down after drone attacks. The Kirishi refinery was offline, while Volgograd and NORSI were reportedly operating at roughly one-quarter capacity.

Ukraine then struck the Yaroslavl refinery on September 17. Reuters reported that the facility halted crude processing after the attack.

Reuters (Reuters)

The campaign has now created a feedback loop that MIL didn’t treat as a major constraint earlier in the war.

Ukrainian strikes reduce Russian refining capacity. Reduced production tightens global diesel supplies. Higher prices create economic pressure outside Russia. Governments supporting Ukraine then gain incentives to influence Kyiv’s target selection.

Trump’s September 13 request that Zelensky stop targeting Russian diesel infrastructure is direct evidence that the loop has become politically relevant.

Reuters (Reuters)

Ukraine therefore faces two separate questions when selecting targets.

The first is whether Ukrainian forces can hit the target. The second is whether the economic consequences of a successful strike will create enough pressure among Ukraine’s partners to limit future attacks.

MIL still assesses the refinery campaign as strategically consequential. The new constraint is that greater effectiveness may also produce greater diplomatic resistance.

Trend: ↑ Strongly rising

Confidence: High

Russia’s changing missile campaign

Russia has also found a new way to increase pressure without exhausting its best missiles.

Reuters reported September 18 that Russia is using RM48U missiles, originally designed as training targets for S-400 air-defense systems, as ballistic strike weapons against Ukraine.

The scale is substantial. RM48Us accounted for more than half of the 228 ballistic and hypersonic missiles fired during July and the first eight days of August, according to Ukrainian government data reviewed by Reuters.

Reuters (Reuters)

The weapons are less accurate than Iskander ballistic missiles, but lower accuracy doesn’t make the strategy irrelevant.

Russia can use RM48Us against lower-value targets while preserving Iskanders and other advanced weapons. Large salvos also force Ukraine to expend scarce interceptors.

Ukraine has nearly exhausted its Patriot interceptor inventory, according to Reuters, while additional interceptors remain in high demand elsewhere.

The resulting contest isn’t simply missile against missile.

Russia is trying to make the cost of Ukrainian defense unsustainable by combining cheap drones, converted missiles, and more capable weapons. Ukraine must decide which threats justify firing a scarce interceptor.

Winter makes the exchange more important. Russia can preserve higher-quality missiles for attacks against electricity, heating, transportation, and industrial infrastructure when cold weather makes damage more consequential.

Trend: ↑ Russian long-range pressure increasing

Confidence: High

NATO escalation and the gray zone

The conventional Russia-NATO war indicator remains low, but the gray-zone indicator rose again.

NATO fighters shot down a drone that entered Lithuanian airspace on September 15. Lithuanian officials said the aircraft may have carried explosives but didn’t initially determine whether Russia deliberately sent the drone into NATO territory.

AP (AP News)

The ambiguity is important.

Lithuanian President Gitanas Nausėda said Russia may be intentionally allowing some drones to stray into NATO airspace as a way to punish countries supporting Ukraine. Poland is making a stronger warning.

Tusk told parliament September 17 that Russia could deliberately stage drone or missile attacks against NATO members and present the strikes as accidents. Tusk argued that ambiguity could delay or weaken the political response inside NATO.

AP (AP News)

France also said this week that Russian hybrid operations are intensifying. President Emmanuel Macron cited drone and cyber threats and ordered planning for stronger protection of French critical infrastructure.

Russia denies Western accusations that Moscow is conducting a hybrid campaign against Europe.

Reuters (Reuters)

MIL continues to treat conventional war and gray-zone activity as separate indicators.

MIL probabilities

• Deliberate conventional Russian attack on NATO in the next several months: below 10% →
• Continued sabotage, cyber operations, drone incursions, infrastructure interference, covert action, or other gray-zone activity against NATO countries: 80–90% ↑

The gray-zone estimate doesn’t represent the probability of NATO-Russia war. MIL is measuring activity designed to pressure NATO while avoiding an unmistakable conventional attack.

The most dangerous scenario is an incident in which Russia expects ambiguity to contain escalation but NATO governments interpret the same incident as deliberate armed aggression.

Sanctions and economic pressure

The sanctions track also moved this week.

The U.S. House passed the Lindsey O. Graham Sanctioning Russia and Iran Act on September 16 after the Senate approved the legislation in August. Trump signed the legislation on September 18.

The law targets Russian energy and defense industries and the Russian shadow fleet. The legislation also gives the president authority to impose tariffs on major countries that continue buying Russian energy.

Reuters (Reuters)

MIL treats the sanctions package as another constraint rather than a standalone war-ending mechanism.

The more important question is how several pressures interact: sanctions, refinery damage, declining fuel exports, military spending, manpower losses, and the continuing cost of replacing equipment.

Russia retains substantial capacity to continue the war. The accumulated constraints matter because Moscow must manage all of them simultaneously.

Trend: ↑ Economic pressure

Confidence: High that pressure is increasing; low that sanctions alone will force a near-term change in Russian war aims

MK-WX weather check

Weather isn’t restricting operations around Sloviansk yet.

Conditions around the northern Donetsk battlefield remain generally dry and mild, with temperatures around the low-to-mid 70s Fahrenheit through the weekend. Rain becomes more possible early next week as temperatures begin dropping.

ISW has already noted that deteriorating conditions and declining foliage are making infiltration more difficult in some sectors.

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The seasonal transition deserves more attention than the immediate forecast.

Drier ground can support mechanized movement, which matters because Russia is reportedly accumulating armor around Dobropillya. Persistent autumn rain would eventually reduce off-road mobility while falling foliage changes concealment for infantry, vehicles, and drone teams.

WX impact this week: Low

Trend to watch: ↑ Seasonal importance increasing

MIL shouldn’t use weather to explain current battlefield movement, but weather could begin affecting Russian and Ukrainian tactical choices during the next few weeks.

CL calibration check

Several September 11 predictions can now be scored more clearly.

Russian operational breakthrough remains unlikely — HIT

Russia didn’t produce the decisive breakthrough MIL considered unlikely. Ukraine instead disrupted Russia’s northern approach toward the Fortress Belt around Lyman.

Renewed negotiations remain likely — HIT

Washington pushed a specific energy-strike proposal this week, and both Kyiv and Moscow publicly engaged with the idea.

The stronger prediction of a meaningful ceasefire remains unresolved.

Limited ceasefire arrangement — PARTIAL HIT

A concrete energy moratorium moved onto the diplomatic agenda, which supports the underlying forecast. Russia and Ukraine haven’t implemented the arrangement, and both continued striking energy targets.

MIL should therefore distinguish negotiating a sector-specific agreement from actually enforcing one.

Direct Russian attack on NATO remains unlikely — HIT SO FAR

No confirmed deliberate conventional Russian attack on NATO occurred.

The Lithuanian drone incident reinforces the importance of keeping accidental, ambiguous, gray-zone, and overt conventional incidents in separate categories.

Russian gray-zone activity remains likely — HIT

European governments reported additional drone, cyber, infrastructure, and other hybrid threats. France now says Russian hybrid pressure has intensified, while Poland is publicly preparing for deliberately ambiguous attacks.

Ukrainian deep strikes will become strategically consequential — HIT, WITH STRONGER EVIDENCE

The evidence strengthened considerably this week.

Three of Russia’s six leading diesel refineries reduced or halted production, another major refinery stopped crude processing after a strike, and the resulting fuel-market pressure was strong enough to produce a public request from Washington for Ukraine to change its target selection.

Calibration result

MIL’s strongest calls remain the deep-strike and gray-zone forecasts.

The battlefield model also performed well by resisting the temptation to extrapolate steady Russian pressure into an imminent operational breakthrough.

The ceasefire model still needs tighter wording. MIL has been better at forecasting the return of negotiations than forecasting whether governments can convert negotiations into enforceable agreements.

CL should therefore continue separating three stages: talks beginning, an agreement being announced, and an agreement actually changing military behavior.

Source check

This week’s strongest evidence comes from refinery operating data, Reuters reporting based on fuel-market sources, publicly documented U.S. legislation, official NATO-country statements, and battlefield assessments supported by geolocated material.

The refinery story is particularly strong because the effects aren’t based solely on Ukrainian battle-damage claims. Reuters independently reported production shutdowns using information from market participants and industry sources.

Reuters (Reuters)

The RM48U assessment is also stronger than a typical battlefield claim. Reuters reviewed Ukrainian missile data and interviewed independent weapons experts, although Reuters couldn’t independently verify every Ukrainian forensic conclusion about individual strikes.

Reuters (Reuters)

The NATO section requires more caution.

Poland’s warning about possible deliberate Russian attacks is an intelligence-based government assessment, not evidence that Moscow has already ordered a specific operation. The Lithuanian drone incident is confirmed, but Lithuania hasn’t established publicly that the airspace violation was intentional.

MIL therefore treats the broader gray-zone pattern as strong while keeping individual attribution claims provisional unless investigators establish responsibility.

Trend board

• Russian territorial momentum: ↓ Weaker
• Ukrainian battlefield position: ↑ Modestly improving
• Negotiation activity: → High
• Limited agreement probability: ↑
• Broad ceasefire probability: → Low
• Ukrainian deep-strike effectiveness: ↑ Strongly
• Political constraints on Ukrainian target selection: ↑
• Russian missile pressure: ↑
• Ukrainian air-defense pressure: ↑ Strongly
• Russian economic exposure: ↑
• Russian gray-zone activity against NATO: ↑
• Direct NATO-Russia war risk: → Low
• Weather influence on operations: → Low now, increasing seasonally

MIL outlook

The dominant MIL scenario remains prolonged warfare with negotiations running alongside escalation.

Ukraine’s counterattack around Lyman weakens one important Russian campaign design without changing the entire war. Russia still has substantial offensive capacity and is preparing additional pressure elsewhere along the Fortress Belt.

The long-range war is moving faster.

Ukraine is imposing measurable costs on Russian fuel production and military infrastructure. Russia is expanding the volume of its missile campaign while exploiting Ukraine’s shortage of Patriot interceptors.

Both strategies are producing second-order effects. Ukrainian refinery attacks now influence global fuel markets and Western diplomacy. Russian missile adaptation increases the burden on Western air-defense production and forces Ukraine to make harder choices about which targets to defend.

The NATO problem is developing along the same lines.

Russia doesn’t need to invade NATO territory to impose costs or test the alliance. Drone incursions, sabotage, cyber operations, infrastructure threats, and ambiguous border incidents can measure NATO’s political and military response while keeping responsibility contested.

MIL therefore sees three increasingly connected contests: the battlefield in Ukraine, the infrastructure war behind the front, and the gray-zone confrontation between Russia and NATO. MIL sees a modest but meaningful improvement in Ukraine’s battlefield position this week.

Operation Vivaldi disrupted Russia’s northern approach toward the Donetsk Fortress Belt and showed that tactical maneuver hasn’t disappeared completely from the war.

The larger strategic change remains the infrastructure contest. Ukrainian strikes are disrupting major Russian refineries badly enough to affect global fuel politics, while Russia is using converted missiles to sustain an increasingly intense air campaign against a depleted Ukrainian air-defense network.

Russian gray-zone activity around NATO remains the most important escalation indicator outside Ukraine. European governments are increasingly treating drone incursions, cyberattacks, sabotage, and infrastructure threats as parts of a persistent campaign rather than isolated events.

CL says MIL’s strongest forecasts remain deep strikes, gray-zone escalation, and the absence of a rapid Russian breakthrough. Diplomacy remains the hardest part of the model to calibrate because negotiations can intensify without producing restraint.

For now, the dominant path remains the same: prolonged fighting, expanding pressure far beyond the front line, rising economic and infrastructure costs, and diplomacy conducted from inside the war rather than after it.