President Donald Trump left open the possibility of pardoning his former campaign chairman, Paul Manafort, in an interview with The New York Post on Wednesday, telling the publication that the option is "not off the table."

"It was never discussed, but I wouldn't take it off the table," Trump told The Post. "Why would I take it off the table?"

On Monday, prosecutors on special counsel Robert Mueller's team accused Manafort of lying to them after having struck a plea deal. A day later, The New York Times reported that a Manafort attorney briefed Trump's lawyers on conversations and details of Manafort's cooperation with Mueller, an unusual arrangement legal experts speculated was to aid Manafort's hopes of a presidential pardon.

Asked about that story, Trump's attorney, Rudy Giuliani, made an accusation to NBC News in a text message that Mueller, who served as FBI director for 12 years, was treating "Manafort like he's a terrorist, incarcerating him before trial, solitary incarceration and repeated questioning."

Reached by NBC News Wednesday night, Giuliani said in a text message that Trump was “not pondering“ pardoning Manafort “now but as any President would he is not surrendering his constitutional responsibilities on the long term.”

Trump, in his interview with The Post, blasted Mueller and claimed that Manafort, former longtime adviser Roger Stone and right-wing conspiracy theorist Jerome Corsi were all asked to lie by the special counsel.

"If you told the truth, you go to jail," Trump said, adding that he does not know Corsi.

Giuliani told The Daily Beast on Wednesday that Trump and Corsi have a joint defense agreement. Giuliani also told the publication that the president "vaguely knows" Corsi — an associate of Stone's and a source for Trump's incorrect claims that Barack Obama was not born in the U.S. — but "doesn't remember the last time they spoke."

“It's actually very brave,” Trump said of Stone, Corsi, and Manafort. "And I'm telling you, this is McCarthyism. We are in the McCarthy era. This is no better than McCarthy. And that was a bad situation for the country. But this is where we are. And it’s a terrible thing,” he continued.

The reference was to the 1950s Army-McCarthy hearings, led by Sen. Joseph McCarthy of Wisconsin, who sought to unearth communists working within the U.S. government. Roy Cohn, who decades later would serve as an attorney for Trump, was the chief counsel for the Senate subcommittee conducting the hearings.

Trump also criticized the practice of "flipping" witnesses — which is when prosecutors get an individual with exposure to admit guilt and cooperate with investigators in exchange for some sort of leniency — just as he did when his former longtime attorney, Michael Cohen, began signaling a willingness to cooperate with Mueller's Russia probe earlier this year after pleading guilty in federal court to a range of charges, including campaign finance violations.

"You know, this flipping stuff is terrible," Trump said. "You flip and you lie and you get — the prosecutors will tell you 99 percent of the time they can get people to flip. It's rare that they can't."