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Firefighters work at houses hit by a Russian air strike in Kharkiv, Ukraine on Sunday.Vyacheslav Madiyevskyy/Reuters

Prime Minister Mark Carney condemned a U.S. deal for Russia to supply millions of barrels of diesel, which he said would fund the war with Ukraine and hurt efforts to end the conflict, even as he subsequently thanked Donald Trump for his work toward a proposed ceasefire.

Mr. Carney spoke with the U.S. President and Ukrainian President Volodymyr Zelensky in separate conversations on Sunday, amid American efforts to broker a ceasefire aimed at protecting energy infrastructure.

The Prime Minister’s Office issued a statement summarizing his call with the Ukrainian leader, in which Mr. Carney attacked Mr. Trump’s diesel agreement. The deal calls for Russia to immediately supply 300,000 tonnes of diesel to U.S. and global markets, with more to be released in the weeks to come.

“The Prime Minister was clear: this agreement is in direct opposition to the efforts of Ukraine, Canada, and our allies to create peace and stability in Europe,” the statement said. “It will provide additional revenue for Russia and help finance its illegal, unjustifiable war against Ukraine.”

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The United States, Canada and other allied countries placed harsh sanctions on the Russian energy industry after the country’s full-scale invasion of Ukraine in 2022, and the White House agreement would involve a partial lifting of those.

The PMO’s statement marked an unusually sharp public rebuke of White House policy on Ukraine by the Prime Minister, whose criticisms of Mr. Trump often don’t mention him or the U.S. by name.

Mr. Carney also broke with Mr. Trump in March, when Canada and other European countries pushed back against the U.S. for easing sanctions on Russian oil.

Later on Sunday, the PMO issued another statement that said Mr. Carney had spoken with Mr. Trump and thanked him for his efforts to broker what the President has described as an “energy ceasefire” between Ukraine and Russia.

Mr. Trump made the surprise ceasefire announcement on his Truth Social platform but offered few details. Mr. Zelensky said he was still waiting to see further elements of the proposal but also said he supported it. There was no word from Moscow about the prospect of a ceasefire.

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“Both parties have agreed. Do not break it!” Mr. Trump’s post said.

Mr. Trump has blamed Ukrainian attacks on Russian oil refineries, rather than his own war on Iran, for increased diesel prices in the U.S., which have become an issue ahead of the midterm elections in November.

Several U.S. lawmakers also criticized the diesel deal. U.S. Senator Thom Tillis, a North Carolina Republican, said the diesel supply deal with Russia may be illegal and will put American lives at risk.

During his call with Mr. Trump, Mr. Carney “expressed Canada’s strong support for this agreement and reiterated President Zelenskyy’s call for Russia to uphold it,” the statement said, referring to the ceasefire proposal.

“It is imperative that all attacks on energy infrastructure and civilians cease immediately,” it continued.

The Prime Minister’s Office did not say whether Mr. Carney raised his concerns about the diesel agreement during the call or if the two leaders spoke about stalled Canada-U.S. trade negotiations.

Meanwhile, Mr. Zelensky said he was looking for some sign that Russia was actually committed to the agreement.

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“Ukraine supports this step, and we have stated so, but now we need a response from Russia – what Russia will say to the American President, and whether it will stop striking our energy infrastructure,” Mr. Zelensky wrote in a posting on X.

Mr. Trump also called for elections in Ukraine, suspended since the 2022 Russian invasion, to which Mr. Zelensky responded that he would call a vote if Mr. Putin agreed to a 60-day ceasefire.

Mr. Zelensky said it was “up to Ukrainians” to choose their leader but added that there needed to be an end to the fighting first. Ukrainian law prohibits elections under martial law for security reasons.

Ukraine’s government reported that attacks by Moscow on energy sites in Ukraine had continued after Mr. Trump’s statement. Still, in a televised evening address, Mr. Zelensky said Ukraine was “ready to refrain from striking Russian energy infrastructure – and we count on the same readiness from Russia.”

With reports from The Associated Press and Reuters