President Donald Trump slammed Senator Jeff Flake calling him “unelectable in the Great State of Arizona.” He also said the senator’s political career is “toast” in a post on Twitter on Sunday night.

Trump made the comments after Flake was caught on microphone criticizing him on Saturday during his conversation with Mesa Mayor John Giles. The Arizona senator said GOP is toast if it becomes the “party of Roy Moore and Donald Trump.”

Flake hosted a town hall meeting at GECO, an aerospace company in Mesa, Arizona. During the event, the senator discussed and answered questions about GOP tax reform bill and possible run against Trump in 2020.

After an hour discussion, he stepped off stage without removing the lapel microphone. The sound from the mic to the speakers was muted. However, the audio from the mic continued to feed to the cameras of ABC 15 Arizona.

The TV station’s camera started to roll in the middle of Flake’s sentence stating his concerned about the future of their party under Trump and Moore. It also caught Giles response. The Mesa Mayor said, “And I am not throwing smoke at you, but you are the guy. Just for fun, think how much fun it would be, just to be the foil you know. And point out what an idiot this guy is.”

According to ABC 15, Giles was referring to Trump in his comment and his office did not dispute it.

In post on twitter, Trump hit back and wrote:

Flake will vote on GOP tax reform bill based on its merits

Flake was among the Republicans critical of Trump. Last month, he delivered a blistering speech against the President and announced his decision not to seek re-election. According to him, the current political environment and leadership in the United States is crude. He said it’s his “obligation” as a “matter of duty and conscience” to criticize Trump.

The Republican Party has a two-seat majority in the Senate. It is currently pushing its tax reform legislation before the end of the year. The Senate Finance Committee already approved the bill and it is heading to the Senate floor for final approval sometime after the Thanksgiving. The House of Representatives passed their version of the GOP tax reform bill last Friday.

On Sunday, Flake’s spokesman Jason Samuels told CNN, the senator is still reviewing the merits of the tax reform legislation. The spokesman said, “How he votes on it will have nothing to do with the President.”