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A frequent Republican critic of President Trump says he's had enough.

FOX's Jared Halpern has more from Capitol Hill:

There are times, Arizona Republican Jeff Senator Flake says, we must risk our careers for our principles. That time, for him, is now:

(Sen. Jeff Flake) "It is time for our complicity and our accommodation of the unacceptable to end."

Flake, who was facing a tough re-election bid next year, will not seek a second Senate term. In an emotional speech from the Senate floor, taking aim at President Trump, Flake warned against reckless, outrageous and undignified behavior.

Flake made his announcement shortly after President Trump left a policy-lunch here at the Capitol with Republican Senators.

On Capitol Hill, Jared Halpern, FOX News.

Follow Jared Halpern on Twitter: @JaredHalpern