Sen. Dick Blumenthal (D-Conn.) responded to a series of tweets sent by President Donald Trump to attack his credibility in light of past false statements he made about his military service. He made the comments to Wolf Blitzer on CNN Monday.

"I have no idea about what is in his mind," he said of the president. "What I do know about is I will not be distracted by this bullying."

"And these bullying tweets reinforce for me the need for a piece of legislation that I am helping to lead with [Sen.] Thom Tillis [R-N.C.] and others," he added, "a bipartisan coalition to prevent the firing of special counsel Robert Mueller whom he has also sought to intimidate."

"And the kinds of statements we've seen about drawing red lines around financial dealings," Blumenthal continued, "about calling the investigation a 'witch hunt' or a hoax and the attacks on the team that Robert Muller has assembled, all point to a looming constitutional crisis if the president proceeds with firing Robert Mueller.

"And that's why preventing it, forestalling that kind of constitutional conflagration is the objective of a group of us, a bipartisan coalition, including both Republican and Democrat colleagues who are intent on sending a message that the rule of law will prevail and nobody is above the rule of law," he concluded, "including the president."

Sen Blumenthal on Trump’s Twitter attacks: “I will not be distracted by this bullying.” https://t.co/qbw9k0DN4N https://t.co/reeuBRehuP

— The Situation Room (@CNNSitRoom) August 7, 2017

Trump began the day Monday assaulting the Democratic senator's reputation with his Twitter account.

Trump was referring to misstatements Blumenthal made that appeared to exaggerate his military service during the Vietnam War.

The president continued Monday evening with this mocking tweet:

Tillis' proposed legislation is called the Special Counsel Integrity Act, and would let  Mueller challenge his firing if the president chose to do so.