Story highlights "I think it's reaching the point where it's of Watergate size and scale," McCain said

The latest controversy has raised questions about whether the President obstructed justice

Washington (CNN) Sen. John McCain invoked Watergate in describing the escalating controversy surrounding alleged ties between President Donald Trump's campaign and Russia.

"I think it's reaching the point where it's of Watergate size and scale, and a couple of other scandals you and I have seen," the Arizona Republican said Tuesday night. "It's the centipede that the shoe continues to drop. Every couple of days, there's a new aspect of this really unhappy situation."

McCain discussed the series of scandals that brought down Richard Nixon's presidency at the International Republican Institute's 2017 Freedom Dinner, where he was being honored. He shared his thoughts about the latest White House news on a panel moderated by former "Face the Nation" host Bob Schieffer.

The New York Times reported Tuesday that former FBI Director James Comey had written a memo describing a meeting he had with Trump, at which the President asked him to end the investigation into former national security adviser Michael Flynn. CNN has confirmed the details of that memo, which has raised questions about whether the President obstructed justice.

McCain's office quickly issued a statement clarifying his remarks Tuesday night.

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