PHOENIX — Things reportedly got a little tense Thursday between presumed Republican nominee Donald Trump and an Arizona senator who has been critical of his campaign.

The Washington Post reports the tense moments between Trump and Sen. Jeff Flake (R-Ariz.) happened during a meeting designed to foster unity among the GOP ahead of the Republican National Convention, which will be held later this month in Cleveland, Ohio.

Flake has been critical of Trump’s campaign, most notably saying his state may vote Democrat for the first time in 20 years if the New York billionaire’s rhetoric against Mexican immigrants continues.

Things were edgy from the onset of the meeting. The Post said Trump acknowledged that Flake had been critical of him and the senator didn’t back down.

“Yes, I’m the other senator from Arizona – the one who didn’t get captured – and I want to talk to you about statements like that,” Flake responded, according to two Republican officials.

Flake was alluding to Trump’s comments last year about Sen. John McCain (R-Ariz.), who spent years as a prisoner of war in Vietnam. Trump said he likes “people who weren’t captured” but later backed down from that stance.

Flake also told Trump he feels uncomfortable endorsing his race, but has not participated in some of the Republican Party’s blatant efforts to halt his campaign that have been dubbed the Never Trump movement.

Trump pointed out to Flake that he had never attacked him, but could begin doing so.

Flake’s office said it did not want to comment further, but confirmed the Post’s story was accurate.

Neither Flake nor Trump mentioned the conflict on social media, but the latter sent a positive tweet after meetings wrapped up.

Just leaving D.C. Had great meetings with Republicans in the House and Senate. Very interesting day! These are people who love our country! — Donald J. Trump (@realDonaldTrump) July 7, 2016

Flake has already said he is not planning on attending the party’s convention.

The solidarity meeting was also marred by other conflicts between Trump and at least two other senators, neither of whom were from Arizona.

Trump predicted all three lawmakers with whom he butted heads would lose their re-election bids, Flake included. His term expires in 2019.

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