Keir Starmer has met with President Volodymyr Zelensky in Kyiv to show his “unwavering support” for Ukraine against Russian aggression.
The Labour leader met with the Ukrainian leader in the capital ahead of next week’s first anniversary of the brutal war.
Earlier on Thursday Mr Starmer travelled to Bucha and Irpin to see the sites of Russian war crimes.
He also met with experts in human rights, reconstruction and appropriations.
Mr Starmer used Prime Minister's Questions last week to push the Government to use frozen Russian state assets to fund the reconstruction.
He also encouraged ministers to ensure that evidence was being collected to help effective prosecutions for war crimes and crimes against humanity.
Speaking after his meeting with President Zelensky, Mr Starmer said: “We were able to discuss the support that Ukraine needs and the justice that it deserves.
“We spoke about the need for that justice to cover both the use of Russian state assets for reconstruction and the need for there to be prosecutions for war crimes.
“I was able to tell him that should there be a change of government when we have a general election here, the support for Ukraine will remain the same.
“It’s a very important message for me to be able to relay to the President face to face, and I’ve been able to do that this afternoon.
“We discussed a range of issues, he’s very concerned about support through weapons and the continuation of training for Ukraine, and I stressed that the Labour Party supports and would maintain the defence, training, and technological support the current UK government is providing.
“I’ve said throughout this conflict there will be no difference between the political parties on this, so we will continue to work with the government to see what further support we can provide.”
A one-minute silence will be held on February 24 across the UK to mark a year since Russia’s barbaric invasion of Ukraine.
The national minute’s silence comes following the historic visit of Ukraine's President Volodymyr Zelensky to the UK last week.
During the visit, the Prime Minister underlined the UK’s steadfast commitment to supporting Ukraine for the long term, ensuring it can secure a lasting peace.
President Zelensky delivered an address in Westminster Hall on Wednesday , the first foreign leader to do so since ex-US President Barack Obama gave a speech there in 2011.
The heroic war leader vowed that "freedom will win" and said victory over Russia would "change the world" in his first visit to London since Vladimir Putin's brutal invasion began nearly a year ago.
Hundreds of MPs, peers, staff and journalists applauded and cheered as he made a passionate address praising the "brave souls" of the UK for their support on behalf of his people.
"I have come here and stand before you on behalf of the brave, on behalf of our war heroes who are now in the trenches under enemy artillery fire ," he said.
"On behalf of our air gunners, and every defender of the sky who protects Ukraine against enemy aircraft and missiles, on behalf of our tank men who fight to restore our Ukrainian borders, on behalf of our conscripts who are being trained now including here in Britain."
Mr Zelensky said London had "stood with Kyiv since day one" and he praised ex-PM Boris Johnson , who was in the audience, for helping to unite allies when "it seemed impossible".
His speech was repeatedly met with applause ringing through ancient hall as he said: "We know freedom will win.
"We know Russia will lose. And the victory will change the world - a change the world has long needed."
