Washington (CNN) A former longtime Republican congressman called Friday for the impeachment of President Donald Trump, who he said is an "illegitimate president."

"I'm calling for impeachment now because the Mueller report is out, and in it (special counsel Robert Mueller) describes 10 obstruction of justice charges that he could not bring because of a Department of Justice rule and regulation that says you can't indict a sitting president -- that's (reason) number one," former Rep. Tom Coleman, who represented Missouri for nearly two decades, told CNN's Erin Burnett on "OutFront."

"Number two, I believe this is an illegitimate President because he welcomed help and influence from the Russians in his campaign," he said. "For example, his (campaign) chairman Paul Manafort met with a Russian intelligence asset in New York and shared with him their polling information and a strategy on how to win the Midwestern states."

Coleman continued: "It's wrong and it needs to be handled and looked at by the Congress because I believe it's an impeachable offense."

The former congressman, who also made the impeachment case Wednesday in a Kansas City Star op-ed, told Burnett he believes Trump is "dismantling our democracy every day brick-by-brick (through) his actions, his lies, his abuse of power."

Read More