While maintaining a consensual tone, the British monarch said an 'unyielding resolve' was 'needed' to defend Ukraine, and reminded his audience of the importance of the rule of law and environmental protection.

The address is a central event of the state visit — the most high-profile of Charles' reign — and will be followed by a state dinner at the White House.

King Charles III acknowledged 'times of great uncertainty' as he addressed the U.S. Congress on Tuesday, marking the 250th anniversary of independence from...