"In the stand we take here, we are in solidarity with all those who are resisting brutal aggression."
Last weekend, Charles' eldest son Prince William and his wife Catherine sent a personal message of support to the people of Ukraine.
In a tweet, they recalled meeting Ukraine's President Volodymyr Zelensky and his wife in October 2020, and hearing of their "hope and optimism" for the country.
"Today we stand with the President and all of Ukraine's people as they bravely fight for that future," they added.
William's younger brother, Prince Harry, and his wife, Meghan, last Friday sent their own message from the United States, where they moved last year after quitting royal life.
"We stand with the people of Ukraine," they wrote on the website of their charitable organisation Archewell, calling Russia's invasion a "breach of international and humanitarian law"