Donald Trump's vanquished GOP presidential rivals who are holding out on endorsing him won't be allowed to speak at the Republican national convention, the presumptive Republican nominee suggested in an interview published Sunday.

"If there's no endorsement, then I would not invite them to speak," Trump said of other top Republicans in an interview with the New York Times.

Among the former Republican presidential candidates who have declined to endorse Trump are Texas Sen. Ted Cruz and Ohio Gov. John Kasich.

Trump may not have the ability, under RNC rules, to prevent Cruz from addressing the assembled party members. But Trump made the comments to highlight the measures he is taking to undercut critics and prevent Republicans opposed to his candidacy from rallying to take the nomination from him at the convention.

"You mean to tell me we're going to get the largest vote in the history of the Republican primaries ... and now the same people that either didn't run or got beaten in a landslide are going to try and back-end?" he said in the interview.

Although both signed an RNC pledge to back the eventual nominee, Cruz and Kasich have withheld their endorsements from Trump.

Cruz, who presented the last legitimate threat to Trump's victory among the crowded field, suffered the toughest criticism doled out by the brash businessman. Cruz, ceaselessly demeaned as "Lyin' Ted" by Trump, has repeatedly declined to say he supports the candidate.

Kasich, meanwhile, has said that he cannot bring himself to vote for Trump. Kasich is the sitting governor of Ohio, the state that will host the convention in July, in the city of Cleveland.