Prime Minister Andy Burnham has travelled to Kyiv as Ukraine marks its Independence Day, in what is his first trip abroad since taking office.
During the visit he is due to co-chair a meeting of the Coalition of the Willing and hold talks with President Volodymyr Zelenskyy.
This year's anniversary marks 35 years since Ukraine declared independence in 1991, and commemorations are taking place against the backdrop of continuing conflict.
“Choosing Kyiv for a first foreign visit sends a clear message to allies and to Moscow about where the priorities lie.”
Downing Street said the trip was intended to underline the UK's continued support for Ukraine and its commitment to working with international partners on security guarantees.
The Coalition of the Willing brings together countries that have pledged to support Ukraine's defence and future security arrangements, including in the event of a ceasefire.
Mr Burnham has said in general terms that support for Ukraine will remain a priority for his government, continuing a cross-party approach in Westminster.
Ukrainian officials have welcomed the visit as a sign that backing from Kyiv's partners remains firm despite changes in leadership.
Security for the trip was tightly controlled, and details of the itinerary were not made public in advance.
Independence Day celebrations in Kyiv have been scaled back since the full-scale invasion, with large public gatherings limited because of the risk of air attacks. Instead, many Ukrainians mark the occasion with flags, traditional embroidered shirts and moments of remembrance for those who have died in the war. Ceremonies were also held in cities across Europe where large numbers of Ukrainian refugees now live.
Further announcements on military and economic assistance are expected following the coalition meeting.
