BERLIN?U2 said Tuesday frontman Bono had been released from hospital after emergency back surgery for temporary "paralysis", as it cancelled its Glastonbury Festival performance and this year's US tour.

"Bono has now been discharged from Ludwig Maximilians-University Hospital in Munich (southern Germany) where he underwent emergency surgery on Friday, following a back injury," the Irish band said on its website.

"This surgery was the only course of treatment for full recovery and to avoid further paralysis," the site quoted one of his doctors, Joerg-Christian Tonn, as saying.

Bono was suffering from severe compression of the sciatic nerve, a serious tear in the ligament and a herniated disc, doctors said. He would need at least eight weeks to recuperate.

U2 tour promoter Arthur Fogel said 16 North American shows planned this year, from Salt Lake City on June 3 to New Jersey on July 19, would be rescheduled for 2011.

"Although we understand the disappointment to U2 fans, first and foremost comes the recovery of Bono," Fogel said.

The website also quoted Bono as telling the head of next month's Glastonbury Festival in England that the band, which was scheduled to headline the event, would have to bow out.

"I'm heartbroken," Bono said. "We really wanted to be there to do something really special -- we even wrote a song especially for the Festival."

Bono, who celebrated his 50th birthday in New York earlier this month, was admitted to a specialist neurosurgery unit last week after injuring himself during tour preparation training in Germany.