White House press secretary Sarah Huckabee Sanders used her news briefing to tear into Corker, saying he had "rolled out the red carpet" for the Iran nuclear deal.
The two-term Republican announced last week he would not seek a third term, which means eventually giving up his coveted chairmanship of the Senate Foreign Relations Committee.
Not to be denied, Corker immediately responded that the Trump White House was nothing more than a daycare center for adults.
"I think I've had four conversations with him about my re-election. he encouraged me to run and said he would do a rally and endorse me", Corker said.
- If Tennessee Senator Bob Corker thought retirement might be the easy way out of Washington, he may have to reconsider his rather surprising decision. I said "NO" and he dropped out (said he could not win without.my endorsement).More news: Sadio Mané Faces Six-Week Layoff Following Hamstring Injury
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Every Republican senator up for re-election in 2018, with the exception of Sen.
"The vast majority of our caucus understand what we're dealing with here. they understand the volatility that we are dealing with and the tremendous amount of work that it takes from people around [Trump] to keep him in the middle of the road", Corker continued.
Trump continued his feud with Corker during a Tuesday meeting with former Secretary of State Henry Kissinger, pushing back on the senator's statement that Trump is putting the United States on a path toward World War III. "Didn't have the guts to run!" After the outbreak of violent protests in Charlottesville, Va., Corker said that he didn't feel that Trump had demonstrated the "competence" or "stability" needed for a successful presidency.
Mick Mulvaney, director of the Office of Management and Budget, said Sunday that he thinks Corker feels free to speak his mind now that he is not seeking reelection. He added, "I know [Trump] has hurt, in several instances, he's hurt us as it relates to negotiations that were underway by tweeting things out".
Corker's comments have already infuriated Trump's base.