However, despite the Watergate comparison, McCain also said he was against appointing a special prosecutor, according to New York Times reporter Maggie Haberman.
McCain was speaking to Bob Schieffer of CBS News at the International Republican Institute dinner hours after news broke that Trump reportedly asked James Comey, who was FBI director at the time, to drop his investigation into former national security adviser Michael Flynn.
According to the Daily Beast, Schieffer asked McCain what advice he would give to Trump.
The senator told the former "Face the Nation" host that he would tell the president "the same thing that you advised Richard Nixon, which he didn't do ... get it all out ... it's not going to be over until every aspect of it is thoroughly examined and the American people make a judgment. And the longer you delay, the longer it's going to last."
McCain also called Russian Foreign Minister Sergei Lavrov "an old KGB apparatchik stooge."