Prime Minister Keir Starmer pledged on Thursday to work with Ukraine and allies to offer Kyiv robust security guarantees if a ceasefire is negotiated with Russia, offering more support to President Volodymyr Zelenskiy with a 100-year partnership deal.

British Prime Minister Keir Starmer arrived in Ukraine Thursday with a pledge to help guarantee the country’s security for a century, days before Donald Trump is sworn in as U.S. president.

The arrival of British Prime Minister Keir Starmer in Kyiv on Thursday morning to sign a “100 year” security and trade agreement was accompanied by the sound of explosions as air defenses fended off an apparent Russian attack.