US presidential primaries: Primary rivals break pledge of support, says Trump

Terming their act as disgraceful, Trump further said that these candidates should never be allowed to run for public office again

Presumptive Republican presidential nominee Donald Trump has said some of his primary rivals have been "disgraceful" in breaking their pledge of supporting him and should never be allowed to run for public office again.

"They signed a pledge saying they will abide, saying they will back the candidate of the party. They broke their word," Trump said yesterday.

"In my opinion, they should never be allowed to run for public office again because what they did is disgraceful," Trump, 70, told his supporters at an election rally in Bangor, Maine.

He, however, refrained from taking any names.

But the rematks came on a day when Governor of Ohio John Kasich wrote an email to his supporters asking for a positive poll for him.

Several of Trump's primary rivals including Ted Cruz and Jeb Bush are yet to endorse him.

A few days ago, Trump had said those primary candidates who do not endorse him should not be invited to address the Republican convention in Cleveland next month.

Trump defeated a crowded Republican presidential field of 16 candidates to win the party's presidential primary.

Meanwhile, a news report said that the supporters of the Bush family are likely to endorse Democratic presidential nominee Hillary Clinton.

"I live in DC so my vote is kind of irrelevant. But if I was the last vote, if my vote was going to make a difference, I'd prefer to have Hillary Clinton in the White House than Donald Trump," Tony Fratto, a former deputy assistant and deputy press secretary to President George W Bush, told 'The Hill'.