Former Gov. Rick Perry, who has seized the mantle as the most vocal Republican critic of Donald Trump's presidential candidacy, upped the ante Saturday by calling for the bombastic billionaire to immediately exit the 2016 race.
Perry's statement came shortly after Trump suggested at an event in Iowa that U.S. Sen. John McCain, R-Ariz., was not a war hero "because he was captured." McCain, a former Navy pilot, was taken prisoner for several years after his plane was shot down during the Vietnam War.
"He's a war hero because he was captured. I like people that weren't captured," Trump reportedly said.
"Perhaps he's a war hero, but right now, he's said bad things about a lot of people," Trump added.
Trump's "comments have reached a new low in American politics," Perry said. "His attack on veterans make him unfit to be Commander-in-Chief of the U.S. Armed Forces, and he should immediately withdraw from the race for President."
Perry's reaction was the swiftest and sharpest of any presidential candidate Saturday. And it fit in with Perry's efforts to prioritize the military vote as a veteran himself who spent five years in the Air Force.
The former governor has already taken on Trump over his remarks last month generalizing people in the country illegally as criminals. Trump has refused to back away from those comments, despite varying degrees of condemnation from Perry and other GOP hopefuls.
And in a statement released Saturday, Trump showed no inclination to back away from his comments about McCain either.
"I am not a fan John McCain because he has done so little for our Veterans and he should know better than anybody what the Veterans need, especially in regards to the VA. He is yet another all talk, no action politician who spends too much time on television and not enough time doing his job and helping the Vets," Trump's statement said.
"I have great respect for all those who serve in our military including those that weren't captured and are also heroes," the statement added.
A Trump spokeswoman did not immediately respond to a request for comment on Perry's call for the businessman to drop out of the contest.
Compared to Perry, U.S. Sen. Ted Cruz was more mitigated in his first public comment on the matter.
"John McCain is an American hero," the Republican presidential candidate tweeted on Saturday afternoon. "Although we have some policy disagreements, I'm proud to serve alongside him."
Abby Livingston contributed to this report.