With many Republican grandees refusing even to endorse Donald Trump for president, let alone speak on his behalf at the party’s upcoming convention, the property mogul’s campaign is reportedly packing the programme not with politicians, but with celebrities.

Among the stars who may take the stage in Cleveland from 18 to 21 July are boxing promoter Don King, New England Patriots quarterback Tom Brady and retired college basketball coach Bobby Knight, who campaigned with Mr Trump ahead of the GOP’s Indiana primary in May.

Mr King, who lives in Cleveland and is a long-time friend of the presumptive Republican nominee, told the Associated Press he would “definitely” be involved in Mr Trump’s coronation. “He’s my man. I love him. He's going to be the next president,” Mr King said.

The two surviving Republican presidents, George HW Bush and George W Bush, have both said they will not attend the convention. Jeb Bush and his fellow 2016 candidate, Ohio Governor John Kasich, also plan to skip the event, as does Mitt Romney, the party’s 2012 nominee.

The line-up at the Quicken Loans Arena won’t be entirely politician-free, however. Mr Trump has said he would like to feature Sarah Palin, who made a splash at the 2008 convention, where she was unveiled as John McCain’s vice presidential running mate.

Republican former House Speaker Newt Gingrich, who is said to be on Mr Trump’s vice-presidential short-list, said inviting celebrities could be a smart campaign move. “Trump understands that if he can appeal to consumer America, he drowns political America,” Mr Gingrich told AP.

When Mr Romney attempted to add some celebrity sparkle to his nomination in 2012, it backfired, with the Republican actor-director Clint Eastwood delivering his now-infamous convention speech to an empty chair.

This year, no celebrity has sufficient star power to overshadow Mr Trump. “What they’ve asked me to do is to speak all three nights. I turned it down,” the reality TV star recently told the New York Times. “I don’t want people to think I’m grandstanding… but it would get high ratings.”

Most of the Trump family are also expected to appear. “My children are all going to be speaking,” Mr Trump told the Western Conservative Summit in Denver last week. “My wife is going to be speaking at the convention. We’re going to have a great time.”

Mr Trump’s eldest daughter Ivanka recently told a radio interviewer that the convention would be “unlike any we’ve ever seen,” adding: “It will be substantive. It will be interesting. It will be different. It's not going to be a ho-hum line-up of, you know, the typical politicians.”