WASHINGTON – President Donald Trump on Friday sought to play down speculation that he had brought acting Attorney General Matthew Whitaker on board to curtail the special counsel investigation, telling reporters that he doesn't know Whitaker and hasn't spoken to him about the probe.

"I didn't speak to Matt Whitaker about it," Trump told reporters as he left the White House en route to Paris. "I don't know Matt Whitaker."

His comments came two days after Trump ousted Jeff Sessions as attorney general and installed Whitaker, Sessions' chief of staff and a former U.S. attorney in Iowa, as the top official at the Justice Department.

The Washington Post reported this week that one of the reasons Trump liked Whitaker was because Whitaker had briefed him on many occasions because the president preferred not to talk to Sessions, whom he had often disparaged publicly.

Since stepping into his new role, Whitaker has faced questions – principally from Democrats – about whether he should recuse himself from overseeing the special counsel investigation into Russian interference into the 2016 election, given that he had previously criticized the probe in opinion pieces and as a television commentator.

Whitaker's appointment has also prompted questions from Democrats about whether Trump brought him aboard to curtail or shut down the Mueller investigation, which is examining possible coordination between Trump's campaign and Russia and potential obstruction of the probe by Trump.

Asked by a reporter if he hired Whitaker to rein in the probe, Trump said: "What a stupid question."

While claiming not to know Whitaker, Trump praised him as a "very strong person with a very strong personality," saying that's what the Justice Department needs at this point.

"Matthew Whitaker is a very smart man," Trump said. "He is a very respected man in the law enforcement community. . . . The choice was greeted with raves initially."

Trump also sought to dismiss the notion that Whitaker should recuse himself of oversight of the Russia probe. Trump suggested he would have few choices for attorney general and other top government posts if he eliminated everyone who had been on television.

"Do we have to hire somebody in a shell? I don't think so," Trump said.

The Post reported Thursday that Whitaker has no intention of recusing himself from overseeing the special-counsel probe, according to people close to him.

Trump also sought to brush off suggestions by some lawyers – including George Conway, the husband of White House counselor Kellyanne Conway – that the Constitution requires Whitaker to be confirmed by the Senate before he starts serving.

Trump claimed that Whitaker was "confirmed at the highest level" because his nomination to serve a U.S. attorney in Iowa had been approved by the Senate.

Trump also complained that Mueller was not subject to Senate confirmation before he began serving a special counsel.

Asked about potential permanent replacements for Sessions, Trump said he likes former New Jersey Gov. Chris Christie, a Republican, but has not spoken with him about the job.

Trump also repeated his frequent claim that the Mueller investigation is a "hoax."

"There's no collusion," Trump said. "It's a whole hoax."

He said the reason he prevailed in the 2016 presidential election is that he was the better candidate and that Democrat Hillary Clinton "didn't know what the hell she was doing."