Four of Michael Jackson's London concerts have been pushed back, with some fans now facing a nine-month delay before they get to see the King of Pop.

Michael Jackson is scheduled to perform 50 concerts at London's O2

Organisers were quick to emphasise that the decision had nothing to do with Jackson's health.

They said the dates were moved due to the sheer magnitude of the spectacle, and the desire for all fans attending the opening nights to get the same high-quality experience planned for all 50 shows.

The first scheduled show at London's O2 Arena on July 8 will now take place a few days later on July 13.

But fans with tickets for three other initial concerts will have to wait around nine months until spring 2010 if they want to make it to the rescheduled concerts.

A show scheduled for July 10 will be moved to March 1, 2010, a July 12 date will be moved to March 3, 2010, and a concert for July 14 will now take place on March 6, 2010.

Randy Phillips, president and CEO of promoters AEG Live, said the decision was a "tough" one to make, but the show, costing more than $20m (£13m), had grown in size and complexity.

Mr Phillips said the date changes had "absolutely nothing to do with (Jackson's) health."

"I would trade my body for his tomorrow," he said. "He's in fantastic shape."

Mr Phillips said there were no plans to change any more dates, although "if Michael were to get ill, that's possible".

Jackson's creative collaborator Kenny Ortega said: "The original plan would have put us into the O2 one night before we opened.

"It just wasn't practical."

He added: "Physically and mentally we're having a blast. We're having a great time.

"This is a high time for Michael. He's loving the creative process."

Mr Phillips said of the show: "It's going to cost us well north of $20m and it's incredible.

"This is one hell of a show. It's going to be worth the wait."

The concert promoters stressed that anybody who cannot make the rescheduled London dates for any reason will receive a full refund of the ticket and booking fee.

Fans can log on www.michaeljacksonlive.com for further information, or call the hotline on 0844 277 9982.