BANGOR, Maine — No peace til Cleveland? Just when some thought the infighting was over, Donald Trump once again is taking on former Republican rivals and traditionally conservative allies.

The GOP presumptive nominee, less than three weeks from the party's convention, told a crowd on Wednesday that he isn't happy that some of his former rivals aren't endorsing him — and the way he sees it, there should be consequences.

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Without naming specific politicians, Trump called those 2016 candidates who have yet to endorse him in accordance with the RNC pledge "sore losers" who "should never be allowed to run for public office again." Among those names yet to officially and explicitly endorse Trump are Ohio Gov. John Kasich, Texas Sen. Ted Cruz, and Wisconsin Gov. Scott Walker. Names that could, come next election cycle, be back in play once again.

For his part, Trump says he "would have honored the pledge" if the roles were reversed. "I wouldn't have gone crazy, I wouldn't have had 'Let's yell it from the loudest building,' but you know what, I would have honored the pledge."