Osbourne was in the UK promoting his duet with daughter Kelly

Osbourne, 55, is on a ventilator after breaking his collarbone, eight ribs and a vertebra in his neck.

He is described as "stable and comfortable", although his doctor has said he could be kept in intensive care for several days.

Osbourne has been visited by his wife Sharon, who flew in from Los Angeles on Tuesday, and his daughter Kelly.

The accident happened on Monday afternoon at Osbourne's £3m estate in Chalfont St Peter, Buckinghamshire. He was treated at Wexham Park Hospital in Slough, Berkshire.

Osbourne cannot speak because of a tube in his throat

His tour manager Bill Greer said Sharon and Kelly had spent some time at his bedside. He said they would not be talking to the media in the immediate future.

"This really is a difficult time for the rest of the family and at this point Sharon really doesn't feel able to come and talk to you directly," he said.

Osbourne's doctor, Dick Jack, said circulation in his left arm had been restored after damage to a blood vessel caused by pressure from his broken collarbone. He was unable to speak because of a tube in his mouth.

Dr Jack said doctors were "very satisfied" with his progress.

"We have begun, slowly begun, the process of getting him off the ventilator. Now this can take several days so there won't be any major changes in his condition for the next 24 hours."

Osbourne was in the UK to promote his latest single - Changes - a duet with his daughter Kelly.

Following the accident, bookmaker William Hill slashed the odds on the song becoming Christmas number one.