“I don’t anymore,” the Republican frontrunner said during a CNN town hall forum in Milwaukee when moderator Anderson Cooper asked if he stood by the pledge. “No. We’ll see who it is.”

“I have been treated very unfairly,” Trump explained, faulting the Republican National Committee and the GOP establishment.

Trump’s dumping of his vow may have seemed abrupt, but there was plenty of warning.

In September, Trump joined other Republican presidential hopefuls by signing a pledge affirming: “If I do not win the 2016 Republican nomination for President of the United States I will endorse the 2016 Republican presidential nominee regardless of who it is.”

But since then Trump has repeatedly wavered, threatening to bolt the party and run as an independent in response to what he calls GOP efforts to undermine his candidacy.

Indeed, his decision to drop the pledge was more a question of when than if. As Republican leaders have plotted efforts to deny Trump the GOP nomination if he falls short of the 1,237 delegates needed to claim the party mantle outright, party officials have assumed the effort would result in Trump denouncing the process as illegitimate, refusing to back the nominee, and attempting a third party bid.

Trump is not alone in his decision to turn his back on the loyalty pledge. His Republican rivals, Texas Sen. Ted Cruz and Ohio Gov. John Kasich have also walked back their own vows to support the nominee if it is Trump.

“If the nominee is somebody I think is really hurting the country, and dividing the country, I can’t stand behind them,” Kasich said Tuesday at the town hall.

“I’m not in the habit of supporting someone who attacks my wife and attacks my family,” Cruz said during the town hall prior to Trump’s appearance. Cruz alleged Trump had a role in causing the publication of an unsubstantiated National Enquirer report suggesting Cruz had extramarital affairs.

Cruz said that nominating Trump would hand the election to Hillary Clinton, due to polls showing the Democrat would trounce Trump. Cruz also vowed that he would defeat Trump in the GOP nomination fight.

Trump noted later that “Cruz he was essentially saying” he would not back Trump as the GOP nominee — a reasonable inference.

Cruz “doesn’t have to support me,” Trump added. “I’m not asking for his support. I want the people’s support.”

The celebrity businessman suggested he wanted to save Cruz and other former rivals from the difficulty of supporting the candidate who beat them.

“I don’t want people to do something against their will,” Trump said.

Trump’s renunciation of his pledge came in a town hall event where he repeatedly exhibited the abrasive character that helps explain his conflict with the Republican establishment.

Trump defended his campaign manager, Corey Lewandowski, who was arrested Tuesday on misdemeanor battery charges for grabbing and bruising the arm of Michelle Fields, at the time a Breitbart News reporter who was trying to ask Trump a question.

“She’s not a baby,” Trump said, arguing that Fields exaggerated the incident.

Trump’s claims were striking because a video, filmed by his own security cameras and released Tuesday by police in Jupiter, Fla., clearly show Lewandowski grabbing and pulling Fields away from Trump. That action appears to violate a Florida battery law that bars touching or striking another person against their will.

The video also flatly contradicts past claims by Lewandowski and Trump’s campaign that the aide did not touch Fields. Trump also suggested Fields “made up” the incident.

But Trump gave no ground Tuesday. He attacked Fields, claiming she “grabbed” him, an incorrect description of images that show her hand appearing to brush him as she questioned him. He said he might file charges against her.

“She had a pen in her hand, which Secret Service is not liking because they don’t know what it is,” Trump added. “It could be a little bomb.”

Trump also continued to defend his retweet of an unflattering image of Cruz’s wife Heidi next to a posed shot of Trump’s wife Melania, a former model. Trump claims his action was justified because an anti-Trump super PAC ran an ad in Utah that showed Melania Trump in a seductive pose to suggest she was unfit to be the first lady.

“Look, Trump said. “I didn’t start it.”

“Sir, with all due respect, that’s the argument of a five-year-old,” Cooper replied.

“It is not,” Trump said.