Russia's attacks on Ukraine's energy sector on Monday night - as temperatures dropped to -20C (-4F) - were "barbaric" and "particularly depraved", UK Prime Minister Sir Keir Starmer has said.

He made the comments after speaking to US President Donald Trump hours after Russia hit power plants and critical infrastructure in the capital, Kyiv, and elsewhere.

It comes at the end of a week-long pause that Trump had asked Russia's President Vladimir Putin to observe as a fierce cold swept Ukraine.

Trump told reporters that Putin had "kept his word" and that he would like him to end the war. US envoys are meeting Ukrainian and Russian negotiators in Abu Dhabi to discuss details of a peace plan.

Asked by reporters on whether he was disappointed with Russia's renewed attacks, Trump said, "it [the agreement] was on Sunday, and he [Putin] went from Sunday to Sunday.

"It's a lot, you know, one week, we'll take anything, because it's really, really cold over there."

The US president has been leading efforts to end the war, but his Russian counterpart has refused calls for a ceasefire.

The damage from Russia's latest attacks has been extensive, with more than 1,000 tower blocks in Kyiv without heating and a power plant in the eastern city of Kharkiv beyond repair.

Residents have been forced to spend the night sheltering in metro stations, with some pitching tents on the platforms to protect them from the freezing cold.

The authorities have been setting up centres around Kyiv for the city's inhabitants to go to warm up. They are also importing more generators in order to cope with longer blackout periods as engineers try to repair damage.

Ukraine's Energy Minister, Denys Shmyhal, has said that the situation with the country's energy system remains "difficult" and that they would take some time to repair.

This includes Kyiv's Darnytsia Combined Heat and Power (CHP) plant, which Shmyhal said had been "severely damaged".

Ukraine has complained repeatedly of a shortage of missiles - urging allies to deliver more.

The Ukrainian Air Force said it was attacked by more than 100 drones early on Wednesday. It added that, while it had intercepted most of these, drone strikes were reported in 14 locations, along with falling debris.

The head of Dnipropetrovsk's military administration, Oleksandr Ganzha, said a 68-year-old woman and a 38-year-old man were killed during a Russian attack. Two other people were injured.

In the Zaporizhzhia region, leader Ivan Federov said three people were killed and 11 wounded, including children, during attacks on Tuesday evening that continued overnight.

The Russian-controlled government in Luhansk said a man and a woman were also killed on Tuesday night in a drone attack, launched by Ukraine, that hit a minibus.

At least one injury was also reported in Odesa during strikes that damaged residential buildings.

In Russia itself, the governor of the western Bryansk region, Alexandra Bogomaz, said Ukraine had launched a "combined attack" including drones and long-range missiles - destroying a residential building and injuring one person.

Further south in Belgorod, close to the border with Ukraine, governor Vyacheslav Gladkov said work was continuing to restore power and water services following a Ukrainian missile strike there earlier in the week.

Meanwhile, top US envoys are meeting negotiators from Russia and Ukraine in Abu Dhabi on Wednesday and Thursday.

US envoys Steve Witkoff and Jared Kushner - Trump's son-in-law - are joining teams of Russian and Ukrainian negotiators to thrash out the US-proposed peace deal.

The most difficult issue on the table concerns Russian demands for Ukraine to cede the rest of the territory of the eastern industrial region of Donbas that Moscow does not currently control.

Russia has made slow progress in the area recently.

It launched a full-scale invasion of its neighbour in February 2022.