Russia and Ukraine have agreed to an "energy ceasefire" effective immediately, US President Donald Trump announced Sunday — a deal that, if it holds, would steady a diesel market stripped of roughly 10% of global seaborne supply by war damage and export bans.

"Both parties have agreed. Do not break it!" Trump wrote on his Truth Social platform, without providing further details. The White House did not respond to a request for clarification on the post.

The announcement landed in a market already bracing for change. Cargoes totaling about 13.5 million barrels of Russian diesel are set to begin moving into global markets this month under a deal Trump struck with Moscow — the first US imports of Russian diesel since March 2022, according to Energy Information Administration data. The arrangement required a Treasury Department waiver lifting sanctions.

Why does the ceasefire matter for fuel markets?

Ukrainian drone strikes on Russian refineries and other energy assets pushed Moscow to impose a temporary ban on exports of most diesel, jet fuel and gasoline in July. Russia extended that ban through October. Before the restrictions and the refinery attacks, Russia supplied roughly 10% of global seaborne diesel.

Withdrawing those volumes compounded disruption to flows through the Strait of Hormuz triggered by the US-Iran war, tightening distillate supply across major importing regions. A genuine halt to attacks on energy infrastructure on both sides would be the first step toward restoring Russian refinery utilization and export availability.

The ceasefire's durability, however, remains unproven. Trump announced a similar energy ceasefire last month; Zelenskyy later said no deal had been finalized, and the war continued.

What did Zelenskyy say?

Ukrainian President Volodymyr Zelenskyy signaled openness to exactly this trade in an interview on ABC's This Week, recorded before Trump's post. "Russia doesn't feel real pressure, they want to continue," he said, adding that he had told Trump and his team Ukraine was ready for a ceasefire. "We are ready to begin from any kind of steps of de-escalation."

That includes an energy ceasefire if Russia agreed to reciprocal steps. "Don't attack us. Don't kill our children," Zelenskyy said. "We will stop attack your diesel."

After Trump's announcement, Zelenskyy said "Ukraine supports the ceasefire, and it is important that Russia support it as well," noting Kyiv was "awaiting details" from Washington. He had previously told Axios the announcement took him by surprise.

How much political friction surrounds the diesel deal?

Considerable. Trump had demanded the day before that Zelenskyy halt attacks on Russian oil refineries and suggested he consider stepping aside as leader. The diesel import deal has drawn bipartisan fire in Washington and condemnation from Kyiv, which sees it as handing Russia more resources to continue the war.

Seven US senators — four Republicans and three Democrats — released a statement noting Congress banned Russian energy imports in 2022 and calling the deal illegal. "President Trump's decision to allow Russian diesel imports to the US runs directly counter to that law," the senators wrote. "The administration has also failed to consult with Congress or submit any explanation to justify its decision as required by statute."

Canadian Prime Minister Mark Carney's office said he had spoken with Zelenskyy and asserted the "agreement is in direct opposition to the efforts of Ukraine, Canada, and our allies to create peace and stability in Europe."

What is the situation on the ground?

The war is well into its fifth year. At least 20 people were killed when Russia struck residential buildings in Ukraine on Saturday, hours after the latest US-hosted talks on ending the invasion were cut short by a day.

For diesel buyers and tanker operators, the near-term question is whether Moscow's export ban lapses after October as planned and whether the 13.5 million barrels already sanctioned by the Treasury waiver proceed regardless of the ceasefire's fate. Traders will be watching Russian refinery output and Black Sea and Baltic loadings through the month for the first hard evidence either way.