President Trump on Tuesday said he would welcome ex-national security adviser Michael Flynn back to the White House despite firing the retired lieutenant general in early 2017 over his contacts with the Russian ambassador to the U.S.

"I would. I think he's a great gentleman," the president told CBS News in an interview. "He's a great — he's been in the military for many, many decades, actually. Highly respected. What General Flynn went through is so unfair."

Flynn was among six Trump campaign associates charged in the course of former special counsel Robert Mueller’s investigation into Russian election interference and the only one to have served in the White House.

Flynn sought to withdraw his guilty plea earlier this year, and the Justice Department, in a highly unusual development, moved to drop charges against Flynn in May, arguing that the former Trump adviser’s lies were not “material” to the investigation and that it could no longer prove its case.

The development was widely scrutinized and triggered concerns among critics about the politicization of the Justice Department under Trump.

Last week, the federal judge in the Flynn case asked an appeals court to rethink its decision ordering the charges to be dropped.

Trump and other conservatives seized on interview notes released in April that showed FBI agents discussing how to approach Flynn’s interview and asking whether the goal was to “get him to lie.” Former prosecutors described such discussions as routine, however.

The president has thus far declined to say whether he will intervene in Flynn's case, noting that it is still playing out. 

"I don't think he's going to need a pardon because he's been proven to be innocent," Trump told CBS. "I don't think he's going to need a pardon."