President Donald Trump has sent a letter of support to Ukraine praising its courage and saying the United States believes in its future as an independent state, as the country marks the anniversary of declaring itself free of Soviet rule.

Russia said power and energy facilities had been targeted by Ukraine, which accused Russia of "spreading manipulations".

The Ukrainian leader held talks with Prime Minister Mark Carney of Canada and was set to meet with President Trump’s envoy, Keith Kellogg, amid continuing diplomatic efforts to end the war.