The King is hosting world leaders at St James’s Palace on the eve of the Ukraine Recovery Conference.
Charles held an audience with figures including Ukrainian prime minister Denys Shmyhal, US secretary of state Antony Blinken, and European Commission president Ursula von der Leyen on Tuesday evening.
They arrived at the palace ahead of the two day conference on Wednesday, where governments will meet to discuss rebuilding Ukraine after the war with Russia.
The 2022 conference, held in Switzerland, established the Lugano Principles, which laid the groundwork for the reconstruction process.
The King was greeted in the gilt-edged Throne Room by Foreign Secretary James Cleverly and Mr Shmyhal, who presented him with a bronze statue commemorating the liberation of Snake Island.
The dramatic liberation is approaching its one-year anniversary at the end of June.
Charles then met with Chancellor Jeremy Hunt, Defence Secretary Ben Wallace and Mr Blinken.