Volodymyr Zelensky arrived at No 10 on Wednesday to an honour guard made up of troops from the Irish Guards, before talks with the Prime Minister aimed at strengthening Britain's backing for Ukraine.
Andy Burnham hosted the Ukrainian president in Downing Street amid what he described as “dark and difficult days” for the war-torn country.
On his arrival, Mr Burnham told Mr Zelensky that Britain is “behind you and that will not change”.
The two men found common ground on Moscow's stance, agreeing that Russia “has no interest in peace”, as the UK seeks to bolster support for Ukraine after Donald Trump suggested Moscow wants a deal to end the war more than Kyiv.
A Downing Street spokesperson set out the discussion in a readout of the meeting, saying: “The leaders began by reflecting on their call on Saturday, and Russia’s blatant indiscriminate attacks on civilians and energy infrastructure since President Trump called for an energy ceasefire.
“It was clear that Russia had no interest in peace, the leaders underlined.”
The talks covered how Ukraine's allies could step up support, with the Prime Minister pointing to faster deliveries of British lightweight multi-role missiles, which have proven effective against Russia's barrage of jet-powered drones.
During the meeting, Mr Burnham confirmed the UK would accelerate the supply of crucial air defence missiles to Ukraine amid “heavy bombardment” from Russia.
He said the UK would continue in its “diplomatic efforts” to secure international supplies of defensive equipment.
Developing new ways of supporting Kyiv on the battlefield would also be a focus, such as retrofitting British capability onto supplies gifted from other nations, he said.
The meeting comes during a period of strained relations between Ukraine and the United States.
Mr Trump eased sanctions on Russian diesel last week as high fuel prices in the US threatened to overshadow November's mid-term elections.
The UK responded to news of the deal by pledging to “maintain pressure on Russia”.
In recent days, the US president has suggested Ukraine needs a new leader. He has also claimed Russian leader Vladimir Putin wants a peace deal more than the government in Kyiv does.
Concerns have also been raised about intelligence sharing from the US. Mr Zelensky has said Kyiv received no warning about Russian missile strikes on Monday and Tuesday.
Speaking in the Commons ahead of the meeting, the Prime Minister said he would seek to restore Mr Trump's support for Ukraine.
During Prime Minister's Questions, Mr Burnham said he was being “careful” in his language after Mr Trump's diesel deal with Russia, because he said he was “laying the ground” for a reconciliation.
He added: “I will listen to President Zelensky carefully, but he won’t be going away from Britain today empty-handed.”
Mr Burnham also said he had asked his ministers to examine other options for supporting Ukraine, telling Mr Zelensky they were “looking at all possible avenues”.
He insisted the Ukrainian president was “prepared to sit down and discuss” the energy ceasefire proposed by Mr Trump, but added: “Sadly, what we have seen from Russia is further attacks on critical national infrastructure in Ukraine.”
He said: “In these moments, Britain will continue to provide you with whatever support we can.”
The Downing Street talks on Wednesday came as Britain moved to speed up missile deliveries and pursue new ways of supporting Kyiv.
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