Republican Sen. Lindsey Graham of South Carolina continued his stalwart defense of President Trump's conduct, saying the president, unlike former President Bill Clinton, did "nothing wrong" that would warrant his impeachment and removal from office.

"What President Clinton did was interfere in a lawsuit against him by Paula Jones and others, hide the evidence, encouraged people to lie. So, to me, he took the legal system and turned it upside down. But it doesn't have to technically be a crime," Graham said on "Face the Nation" Sunday. "What President Trump did here was completely cooperate in an investigation, a million documents, let everybody that the special counsel wanted to talk to be interviewed."

"I believe the president did nothing wrong. Whether you like him or not, I'll leave that up to you," he added.

Graham, who has become one of the White House's strongest allies in Congress, was one of the leading Republican lawmakers advocating for Clinton's impeachment and conviction in the wake of independent counsel Ken Starr's report, which said the president lied during a sworn deposition about an extramarital affair he had with White House intern Monica Lewinsky.

In January 1999, Graham suggested a president could be impeached even if he or she did not violate any laws, saying the purpose of the rare congressional procedure is about "cleaning the office" of the president. "You don't even have to be convicted of a crime to lose your job in this constitutional republic if this body determines your conduct as a public official is clearly out of bounds in your role," he said at the time.

While special counsel Robert Mueller did not find the Trump campaign committed criminal conspiracy to collude with the Russian government, he detailed in his report a series of efforts by Mr. Trump to derail an investigation he believed would undermine his presidency. Mueller said White House aides either ignored or refused to carry out the president's directives to impede the Russia inquiry.

In his "Face the Nation" interview on Sunday, Graham indicated the scenarios are different, daring House Democrats to impeach Mr. Trump if they believe he committed high crimes and misdemeanors — the standard enshrined in the Constitution for impeachment proceedings.

"So here's the deal for me: You actually have to do something. Bill Clinton lost his law license for five years because he did something," he said. "But to my Democratic friends, if you agree with the 1999 statement I made, [and] you think this office needs to be cleansed, impeach him. It's up to you."