'White House has become an adult day care center': GOP senator in war of words with Trump Republican Sen. Bob Corker is in a war of words with President Trump.

 -- Sen. Bob Corker of Tennessee hit back at President Donald Trump today in what has become a war of words between the two Republicans, with Corker saying that the White House has become an "adult day care center."

The tweet comes after Corker drew attention Wednesday by saying, "I think Secretary [Secretary of State Rex] Tillerson, Secretary [of Defense Jim] Mattis and chief of staff [John] Kelly are those people that help separate our country from chaos."

Trump on Sunday morning used Twitter to slam Corker. The senator's second term will end in January 2019, and and he has said he won't run for re-election.

The president claimed in his tweets that after he turned down Corker's requests for an endorsement and appointment as secretary of state, Corker decided not to run again.

In a statement to ABC News, Corker's chief of staff, Todd Womack, disputed Trump's claims.

"The president called Sen. Corker on Monday afternoon and asked him to reconsider his decision not to seek re-election and reaffirmed that he would have endorsed him, as he has said many times," Womack said.

Corker is the chairman of the Senate Foreign Relations Committee. Despite his decision against running for re-election, he could be a crucial vote in the Senate over the next 15 months on issues such as Trump's planned tax overhaul.