KYIV, Ukraine -- Ukrainian President Volodymyr Zelensky said Russian strikes had hit energy infrastructure across his country hours after President Trump declared an energy ceasefire between the warring sides.

The Russian attacks -- including on gas infrastructure, a power plant and a substation -- come as the U.S. heaps pressure on Ukraine to stop striking Russian oil refineries, and after Trump moved to allow Russia to export diesel to the U.S. in a bid to drive down American prices at the pump.

"Last night, Russian oil refineries were not burning. But at midnight, a Russian jet-powered Shahed struck a gas-production facility in Ukraine," Zelensky said in an address to the Warsaw Security Forum on Monday. "And there was also a Russian strike on an ordinary gas station, involving several drones."

Ukraine has long maintained that it would be prepared to halt drone and missile strikes on Russian oil facilities if Moscow stops its bombing campaign against Ukraine's energy infrastructure, which has already caused widespread power cuts this fall.

Zelensky reiterated that pledge Monday, adding that European and other leaders support that approach. "If Russia wants us to stop our long-range strikes against its oil refineries and oil exports, then Russia must stop its strikes against our energy system and critical infrastructure. And stop killing our people," he said.

Kremlin spokesperson Dmitry Peskov said Monday that he couldn't share any comments regarding the announced energy ceasefire as contacts continued, according to Russian state news agency TASS.

Overnight, a Russian jet-powered drone attack damaged critical equipment at a gas infrastructure facility in the Kharkiv region, Ukrainian state oil-and-gas company Naftogaz said.

Another attack damaged a power substation in the northern region of Zhytomyr, Ukrainian Foreign Minister Andrii Sybiha told journalists at a European Union foreign ministers meeting in Luxembourg.

"No one should believe Putin's words. Look at his actions instead," Sybiha said, reiterating Ukraine's readiness for a reciprocal energy ceasefire.

In an attempt to draw the attention of American decision makers to Russian ceasefire violations, Zelensky said an effective energy ceasefire could be "a major step toward ending the war" if the U.S. steps in to ensure Russia abides by it.