Bono's bad back could end up costing U2 hundreds of millions, says a new report.

Fears are now being expressed that the European leg of the tour may also not happen.

The singer had made it clear that he will not come back until he has his old mobility and  what friends describe the "the full-on Bono treatment."

An inside source told The Irish Times that the future was very cloudy. The European leg was still on , contingent on the lead singer’s recuperation.

"He won’t want reminding that he just turned 50 last month,” said an insider source.

“He has been throwing himself around stages for over 30 years. He’s up there as the front man for two and a half hours a night, and he’s not one to do things by half measures.

“This is a very serious injury and sounds like it could be the result of cumulative damage. How things play out will be interesting. This is showbiz – hundreds of millions of dollars rest upon a 50-year-old man’s back disc.”

Over a million tickets had been sold for the U.S. part of the tour.

Already, the band will be feeling heavy losses, says the band insider.

 “Bono’s back has put them out of action for two months. They’re insured for show postponement, but that’s not the full story. The set-up costs of the three Claws they use was phenomenal.

“They don’t need this, their insurance company doesn’t need this and the global touring economy doesn’t need this. It’s not just the show day; it’s the three of four days before setting up the stadium, one day stripping it down after, the 200 trucks, the drivers, the security, the merchandising people, the drinks and food people, the program sellers, costume, make-up and hundreds of other people.

"U2 would have over 100 permanent touring personnel and an extra 200-300 working personnel at each local venue. It’s the hotels, the flights, the food vouchers. It’s like a small country coming to a standstill.”

Arthur Fogel, chief executive of U2’s concert promoter, Live Nation, said the following about  the 360 tour postponement: “There’s no question this is monumental.”

The band was particularly keen to pass The Rolling Stones tour of 2005 to 2007, which grossed $558 million. The 360 tour would easily have surpassed that.

With their latest album not selling as well as expected, the tour has exceeded expectations. It was the most profitable tour of last year, but in this, its second year, it was supposed to resolve a long dispute over who is the most popular live rock band of all time.