UK Prime Minister Andy Burnham on Sunday backed US President Donald Trump on what he described as his call for an energy ceasefire between Ukraine and Russia.

Earlier Sunday, Trump announced that Russia and Ukraine had agreed to halt strikes on each other's energy infrastructure, surprising Ukrainian leader Volodymyr Zelensky. Russia has not so far confirmed the deal.

"Russia has intensified its strikes on Ukrainian energy infrastructure over the weekend," Burnham posted on X.

"This is an attack on Ukrainian civilians, plunging them into cold and darkness.

"The UK strongly supports President Trump's call today for a sustained energy ceasefire to start now," he added.

He had discussed the issue with Zelensky on Saturday, said Burnham. "Ukraine is ready if Russia stops its attacks.

"This is the best route to get energy and fuel back into world markets."

Trump's statement came two days after he announced a temporary easing of US sanctions on Russian diesel, prompting outrage from Ukraine and its European allies, who argued it only emboldened Russia's President Vladimir Putin.