Ukraine has condemned a fresh wave of Russian strikes overnight, which killed one person and injured 23 others, as talks with the US aimed at ending the war are set to resume.

Ukraine's Foreign Minister Andrii Sybiha said the "brutal" attack - "cynically" ordered by Russian leader Vladimir Putin -had "hit not only our people, but also the negotiation table".

Delegations from Russia, Ukraine and the US have been meeting in Abu Dhabi for the first trilateral talks since the Kremlin launched a full-scale invasion of its neighbour in 2022.

A source told the BBC that some progress had been made but the key issue of territory remains unresolved.

The mayor of Ukrainian capital Kyiv said one person had died and four had been wounded while Kharkiv's mayor reported that 19 people had been hurt during a sustained assault on the city in the early hours of Saturday morning.

On the second day of the three-way talks in Abu Dhabi, Sybiha said the "barbaric" overnight assault proved "that Putin's place is not at the board of peace, but at the dock of the special tribunal".

US President Donald Trump said last week that Putin had accepted an invitation to join his Board of Peace - an organisation focused on ending global conflicts. Putin has not confirmed this.

Kyiv's mayor Vitali Klitschko said on Telegram that three of the four people who had been injured had been hospitalised.

He added that the capital's critical infrastructure had been damaged, leaving 6,000 buildings without heating.

Temperatures have fallen to around -12C in parts of Ukraine. In a statement following the assaults, President Volodymyr Zelensky said: "The main target of the Russians was the energy infrastructure."

Last week, Russia attacked Kyiv's power infrastructure, forcing Zelensky to initially call off his trip to the World Economic Forum in Davos, Switzerland.

In Kharkiv, Mayor Ihor Terekhov said 19 people had been injured during the strikes in the early hours of Saturday morning. A maternity hospital and a hostel for displaced people were damaged.

Russia occupies roughly 20% of Ukraine, including parts of the eastern Donbas region. The Kremlin wants Ukraine to hand over large areas of the territory, but Ukraine has ruled this out.

In Davos, Zelensky said: "It's all about the land. This is the issue which is not solved yet."

He said that he had reached an agreement with Trump on future US security guarantees for Ukraine in the event of a deal.

He gave no detail but said it would need to go before US Congress and the Ukrainian parliament before signing.

The day before the talks in Abu Dhabi began, US special envoy Steve Witkoff and Trump's son-in-law Jared Kushner met with Putin in Moscow.

After the four-hour meeting, Kremlin aide Yury Ushakov said: "Vladimir Putin has emphasised Russia's sincere commitment to settling the Ukraine crisis by political and diplomatic means."

But he said "bringing about a lasting settlement would be unlikely without addressing the territorial issue based on the formula as agreed in Anchorage".

Last August, Trump and Putin met in Anchorage, Alaska to discuss ending the war, resulting in an agreement to allow Russia to take the Donbas region and keep control of the Crimean peninsula, which it allegally annexed in 2014.

Zelensky ruled out giving up the Donbas which is made up of Luhansk and Donetsk and has been partly occupied by Russia for 12 years.

Following the first day of talks in Abu Dhabi, Rustem Umerov, who is leading the Ukrainian delegation, said on social media: "The meeting focused on the parameters for ending Russia's war and the further logic of the negotiation process aimed at advancing toward a dignified and lasting peace."