UK Prime Minister Keir Starmer has arrived in Kyiv to sign what Downing Street is calling a "landmark 100-year partnership" with Ukraine.
The pact would formalise economic and military support already pledged to the country, and offers more, BBC reported.
It is the British prime minister's first visit to Ukraine since taking office last summer, in a show of support for Ukraine days before Donald Trump re-enters the White House.
Ukrainian President Volodymyr Zelensky is keen to discuss firm security guarantees from key allies such as the UK, wary that a new US administration could start pushing Ukraine to make peace with Russia.
Unlike other prime ministers who have rushed to Kyiv, Keir has taken his time to visit, but after six months in office he has come to Ukraine pledging long-term support against what he calls Russia's "illegal and barbaric invasion".
He was greeted at Kyiv railway station by the UK's ambassador to Ukraine, Martin Harris, and the Ukrainian envoy to London, Valerii Zaluzhnyi.
Volodymyr Zelensky has previously said he is looking towards the UK for help getting security guarantees to deter future attacks.
bd-pratidin/GR