Prime Minister Keir Starmer is due to meet President Xi Jinping at the G20 summit in Brazil, with the government revealing it wants “stable and pragmatic engagement” with China.
This will make it the first time a UK prime minister has met with the Chinese president in person since 2018.
Speaking to reporters on his way to the summit in Rio de Janeiro, Keir said “shoring up support for Ukraine” was on the top of his plans.
Meanwhile, Downing Street said the prime minister will urge other G20 nations to step up their support for Ukraine or face “unfathomable consequences” if Russia emerged victorious.
The summit is coming after large scale missile and drone attacks by Russia across Ukraine over the weekend, and will take place as the conflict approaches its 1,000th day.
It is also following reports that the US sanctioned the use of long-range missiles it provides Ukraine for it to strike Russia.
So far, the weapons have only been used by Kyiv on Russian-occupied targets within its own territory.
The UK has also supplied Ukraine with Storm Shadow missiles and defence officials and ministers have for months been making the case for Kyiv to be allowed to use them to hit targets inside Russia, but they’re waiting for the White House to change its mind.
Sir Keir and President Xi had spoken over the phone in August, after Labour’s election victory the previous month, but they have yet to meet in person.
China’s military support for Russia’s war in Ukraine has drawn criticism from the UK and other Western countries.