U.S. President Donald Trump said Sunday that Russia and Ukraine had agreed to an "energy ceasefire," but offered no details on its terms.

Trump's brief social media post said only that the ceasefire took effect immediately and that both sides had agreed to it. "Do not break it!" he wrote. Neither Moscow nor Kyiv immediately commented on the announcement, and The White House did not immediately clarify the president's post or add detail.

His announcement came as Ukrainian President Volodymyr Zelenskyy, in an interview aired Sunday, said Ukraine was ready to stop striking Russian refineries if Moscow halted attacks on Ukraine's energy system, and asked Trump to press the Kremlin to agree.

"We are asking President Trump, (to) give them (a) signal, not (to) attack energy infrastructure of Ukraine," he told ABC's "This Week."

Trump spars with Zelenskyy

Trump said Saturday it was time for Ukraine to get a new president, suggesting Zelenskyy has not done enough to end the war and blaming him for high diesel prices in the U.S.

Zelenskyy said in response to Trump's comments that Ukraine could hold elections if Russia agreed to a 60-day ceasefire. "Give us two months, 60 days off. Total ceasefire, 60 days, and we will organize elections," he said, adding that Ukraine would be ready to accept whatever choice its people made.

"With all respect to President Trump, it's up to our society, up to our people to choose one or another leader," he said. Zelenskyy added that holding a vote during the war would be unlawful and that Ukraine would need security guarantees to allow people to vote safely.

Ukraine has been under martial law since Russia's full-scale invasion in February 2022, and the Ukrainian Constitution bars elections while it remains in force. Beyond the legal barrier, a nationwide vote would be vulnerable to Russian missile and drone attacks, and organizing one is widely seen as logistically impossible, with roughly a fifth of the country under occupation, millions of Ukrainians displaced abroad and soldiers on the front line. Zelenskyy's term formally expired in May 2024, but the constitution allows him to remain in office until a new president is sworn in.

The exchange came as Kyiv pressed its campaign against infrastructure deep inside Russia, with a drone attack on Sunday shutting down a data center run by Russian technology giant Yandex, the third strike on the company's facilities in four days. Russia and Ukraine are locked in a long-range aerial war while their armies remain largely deadlocked on the front line.

The U.S. president, who on Friday struck a deal with Putin to buy diesel from Russia in an attempt to address high fuel prices ahead of U.S. midterm elections, has been urging Zelenskyy for weeks to stop strikes on Russian energy infrastructure.

He has sought to blame record U.S. diesel prices on Ukraine rather than the U.S.-led war in Iran, which has driven up world energy prices. Ukrainian and European officials reacted to the diesel deal with dismay, saying it will help pay for Russia's war effort.

Ukrainian strike on Russian data center triggers outages

The Ukrainian drone attack on the Yandex data center in the city of Vladimir, east of Moscow, caused outages across the company's services, leaving users in dozens of Russian cities and in Kazakhstan, Belarus and Armenia unable to order taxis or access banking services, according to Russian independent news outlet Astra.

"As a result of the drone attack, the infrastructure of Yandex's data center in Vladimir was damaged. Operations at the data center have been completely halted. There were no injuries," said the Yandex Cloud Telegram channel, which provides operational updates on service availability.

In Moscow, residents described disruption to everyday tasks. Pavel Belyavskiy, a driver for Yandex Taxi, said it was unclear whether orders were coming through at all, and that on several rides he had to cancel after waiting a long time because he could not reach the passenger.

"I'd press the 'call' button to contact them, but nothing happens," he said, "There's nothing I can do, so I'm just forced to cancel."

Igor Mann said he went to check the status of an order on the Yandex Market shopping platform but the page was unavailable, and connecting through a VPN did not help. "Nothing worked," he said.

Another Moscow resident, Eduard Malyavko, said the outages had "direct impact" and weren't just about "convenience."

"It's also about work," he said, adding that they also affected "healthcare, and everything else."

On Thursday, a drone attack took a Yandex data center offline in the Ryazan region, southeast of Moscow. A day later, Ukrainian drones hit the company's major data center in the Kaluga region, southwest of Moscow, partly putting it out of action, Yandex said.

Yandex, often described as Russia's Google, runs the country's most popular search engine and a wide range of digital services, and is heavily involved in Russia's artificial intelligence development.