FILE PHOTO: Sen. John McCain (R-AZ) speaks at a press conference about the National Defense Authorization Act in Washington, U.S., October 25, 2017. REUTERS/Aaron P. Bernstein/File Photo

WASHINGTON (Reuters) - Republican U.S. Senator John McCain on Monday called President Donald Trump’s meeting with Russian President Vladimir Putin in Helsinki “a tragic mistake” and a new low point for the United States, accusing the American leader of failing to defend his country.

“Not only did President Trump fail to speak the truth about an adversary; but speaking for America to the world, our president failed to defend all that makes us who we are - a republic of free people dedicated to the cause of liberty at home and abroad,” McCain wrote of Trump, a fellow Republican.

“It is clear that the summit in Helsinki was a tragic mistake,” he added in a statement.