U.S. President Donald Trump faced outrage on Tuesday for his failure to hold Russia accountable for meddling in the 2016 U.S. election, and some U.S. lawmakers threatened action in Congress to punish Moscow and show support for U.S. intelligence agencies.

At a joint news conference with Russian President Vladimir Putin after a summit in Helsinki on Monday, Trump stunned politicians back home by shying away from criticizing Putin for Moscow's efforts to undermine the election, contradicting the findings of American intelligence agencies.

Trump, whose summit with Putin concluded a week-long Europe trip that included a NATO meeting and talks with British Prime Minister Theresa May, pushed back on Tuesday at the storm of criticism, blaming media coverage.