Michael Flynn (Timothy A. Clary/Getty Images)

President Donald Trump's legal team is mounting a credibility attack on former National Security Adviser Michael Flynn, with plans to portray him as "a liar seeking to protect himself if he accuses the president or his senior aides of any wrongdoing," The Washington Post reported Wednesday.

"He's said it himself: He's a liar," one person working on the strategy told the Post.

Flynn's attorney, Robert Kelner, declined to comment.

Ty Cobb, President Trump's private attorney overseeing the response to Russia special counsel Robert Mueller's investigation, also declined to comment.

The Post said its report was based on "three people familiar with the strategy."

The approach would mark a sharp departure from Trump's generally sympathetic approach toward Flynn, 58, a retired Army lieutenant general.

In February, Trump called Flynn a "wonderful man" after firing him over his inaccurate disclosures to Vice President Mike Pence about his Moscow contacts.

The president also refused to discuss whether he would consider pardoning Flynn, telling reporters Dec. 15: "I don't want to talk about pardons for Michael Flynn yet.

"We’ll see what happens," Trump said. "Let’s see.

"I can say this: When you look at what’s gone on with the FBI and with the Justice Department, people are very, very angry."

Flynn pleaded guilty this month to lying to the FBI as part of the Russia probe, which carries a maximum penalty of five years in prison.

He is cooperating with Mueller's team — and prosecutors have said they would, in turn, recommend a sentence from zero to six months in prison.

Flynn's son, Michael Flynn Jr., who was his father's chief of staff, also faced possible criminal charges, the Post reported, but he was spared by prosecutors.

According to the Post, Trump's legal team planned to seize on the elder Flynn's plea deal for a possible defense — though they remain privately confident Flynn does not have evidence to implicate the president or members of his White House.

In court filings, Flynn admitted he lied to the FBI about conversations he had with then-Russian Ambassador Sergey Kislyak during the December 2016 transition.

One of Flynn's brothers, Joseph, urged President Trump to pardon him, taking to Twitter on Tuesday to allege bias at the FBI:

Joseph J. Flynn@JosephJFlynn1

Replying to @realDonaldTrump @foxandfrlends

Mr. President, I personally believe that a pardon is due to General Flynn, given the apparent and obvious illegitimacy of the manner in which the so called "crimes"he plead guilty to were extracted from him. I ask for quick action on this. Thank you and keep up the good work!