U.S. President Donald Trump has issued an ultimatum to NATO allies, stating he will impose major new sanctions on Russia only if all member nations immediately stop purchasing Russian oil and join in the measures to pressure Moscow into ending its war in Ukraine, while also calling for collective 50-100% tariffs on China to sever its economic support for Russia.

In a Truth Social post framed as a "letter to all NATO nations and the world" on Saturday, Trump expressed shock at allies continuing to buy Russian oil, arguing it undermines the alliance's leverage. "I am ready to do major Sanctions on Russia when all NATO Nations have agreed, and started, to do the same thing, and when all NATO Nations STOP BUYING OIL FROM RUSSIA," he wrote, adding that NATO's commitment to "WIN" the conflict "has been far less than 100%." He proposed NATO-wide tariffs on China, Russia's largest oil buyer, to "weaken its economic grip over Russia," claiming compliance would end the war "quickly." "If NATO does as I say, the WAR will end quickly. If not, you are just wasting my time," Trump concluded.

Trump's demands come amid stalled peace efforts, including his August meetings with Russian President Vladimir Putin in Alaska and Ukrainian President Volodymyr Zelenskyy in Washington, with little progress on key issues like territorial concessions. Zelenskyy has welcomed penalties on Russian oil buyers, telling ABC News last week that continued purchases by partners like India and China are "not fair," supporting tariffs to isolate Moscow. Trump recently imposed 50% tariffs on India for its Russian oil imports, straining ties, but has spared China so far.

NATO's oil imports from Russia have plummeted since the 2022 invasion, with the EU banning seaborne crude and refined products, dropping Q1 2025 imports to $1.72 billion from $16.4 billion in Q1 2021. Exceptions persist for landlocked Hungary and Slovakia via pipelines, and Turkey ranks as the third-largest buyer after China and India.

Implementing Trump's full demands would require alliance consensus, unlikely given economic dependencies and past reluctance to escalate energy sanctions due to global market risks. The post follows heightened NATO-Russia friction, including Wednesday's unprecedented drone incursions into Polish airspace during Russia's largest barrage on Ukraine, prompting Poland and Romania to scramble jets and elevate alerts Saturday.

Russia claimed advances in Dnipropetrovsk, capturing Novomykolaivka—a claim unverified by Ukraine's DeepState map. Zelenskyy accused Putin of seeking full occupation, rejecting territorial concessions.