Sir Bob Geldof is warning a new musical based on the story of Live Aid “better not be s***”.

The Boomtown Rats frontman, 71, is set to see the story immortalised on stage of how and Midge Ure put on the iconic Live Aid concerts in London and Philadelphia on 13 July, 1985, to raise money for the Ethiopian famine – during which he famously told TV views of the shows: “Give us your f****** money.”

While giving his approval for ‘Just for One Day’ – which will premiere at London’s Old Vic theatre on 26 January – the straight-talking singer told reporters: “If this musical encourages just one person to have a positive impact for the better, then it will be a job well done.

“I’m looking forward to seeing it at the Old Vic – it better not be s***!”

He insisted in a chat with the BBC the show was not a “tribute thing”, adding: “I wouldn’t have anything to do with that.

“So, there isn’t a person dressed up as (Live Aid performer ) Freddie (Mercury) wearing a c*** moustache. The songs drive the drama along.”

Bob said about how he will be played by 44-year-old ‘Doctor Who’ actor Craige Els in the show: “It’s bad enough being Bob Geldof. It’s slightly worse seeing someone else pretending to be you.

“The one upside for me is that he’s got an amazing voice, so people will think I actually sing as good as that.”

Matthew Warchus, the Old Vic’s artistic director, said: “We all remember where we watched Live Aid, who we watched it with, and the pure amazement at the feat that was unfolding before our eyes.

“It’s these memories and individual stories that are the beating heart of ‘Just for One Day’, and I can't wait for audiences to share in a moment that galvanised the globe once again.”

The plot of ‘Just for One Day’ – which takes its name from a line in

David Bowie’s hit ‘Heroes’ – combines a behind-the-scenes look at how Band Aid and Live Aid came together to put on the ’85 gigs.

Bob added: “The story is based on actual testimony from the day, real people telling their story, so it’s complex theatre.”

The stage adaptation was written by British author John O’Farrell and will be directed by Luke Sheppard and feature music from Bob Dylan, The Who, U2, The Police and The Pretenders, as well as Status Quo, Bryan Adams and Diana Ross.

Live Aid has been hailed as a moment that brought together 1.5 billion people through music.

The Band Aid Charitable Trust has given its permission for the musical to go ahead and will receive 10 per cent of the ticket sales.

It will tell how the concert at Wembley Stadium was put on, at which 70 global artists performed, with more than 1.5 billion people watching the live broadcast. The concert, along with a second gig in Philadelphia, raised £105 million for famine relief.

Live Aid was conceived by Bob after he was moved and infuriated by images of starving people in Ethiopia and came on the back of the astonishing success of charity single ‘Do They Know It's Christmas?’ written by the musician and producer Midge, 69.

Bob said writer John, 61, and director Luke had approached him, saying: “We know you are going to say no, but we want to do it because our dads have never stopped talking about this day.”

David Bowie, Sir Elton John and George Michael were among the stars who performed at Wembley, with Queen’s Freddie Mercury’s act considered the top performer of the day.

Bob acknowledged Queen as “absolutely the best band of the day” with their 21-minute set.

After the concert, he said: “They understood the idea exactly, that it was a global jukebox. They just went and smashed one hit after another. It was the perfect stage for Freddie: the whole world.”