President Trump Donald John TrumpBiden leads Trump by 36 points nationally among Latinos: poll Trump dismisses climate change role in fires, says Newsom needs to manage forest better Jimmy Kimmel hits Trump for rallies while hosting Emmy Awards MORE on Sunday took aim at Sen. Jeff Flake Jeffrey (Jeff) Lane FlakeJeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Republican former Michigan governor says he's voting for Biden Maybe they just don't like cowboys: The president is successful, some just don't like his style MORE, blasting the Arizona Republican for comments he made about Trump on Saturday and claiming Flake's political career is "toast.”

In a tweet, Trump branded the senator "Jeff Flake(y)" and called him "unelectable."

Sen. Jeff Flake(y), who is unelectable in the Great State of Arizona (quit race, anemic polls) was caught (purposely) on “mike” saying bad things about your favorite President. He’ll be a NO on tax cuts because his political career anyway is “toast.” — Donald J. Trump (@realDonaldTrump) November 19, 2017

On Saturday, a live microphone picked up Flake warning that the Republican Party will be "toast" if it becomes the party of President Trump and GOP Senate candidate Roy Moore.

ADVERTISEMENT

"If we become the party of Roy Moore and Donald Trump, we are toast," Flake told his friend, Mesa Mayor John Giles, according to a recording picked up by a KNXV microphone.

The president has repeatedly and publicly aired his dislike of Flake, a vocal critic who refused to support Trump during the 2016 election.

The two have become entangled in Twitter war of words, slamming one another's policies.

Republicans, who have a two-seat majority in the Senate, are in the middle of pushing their tax-reform plan and other top legislative priorities before the year’s end.

Trump claims Flake, who announced last month that he would not seek reelection in 2018, will vote against the GOP's tax-reform proposal. Flake, however, has not publicly stated whether he will or will not support the measure.

Flake has also torn into his own party, accusing it of abandoning its core principles during a speech on the Senate floor.