George Michael and his American lover Kenny Goss have called off their gay 'wedding' after the pop star was discovered having an illicit encounter with a stranger in a London park.

The couple had been looking forward to an Elton John-style 'wedding' ceremony followed by a lavish party to mark their 10th anniversary.

But plans for the nuptials have been called off after the singer was seen emerging from bushes following a sexual encounter with a pot-bellied, jobless van driver.

'They are reassessing their relationship at the moment so there are no immediate plans. Things are very much up in the air,' a source told the Daily Mail.

Michael admitted he was gay in 1998 after Californian police arrested him for lewd conduct in a public lavatory. He later poked fun at the incident in his song Outside.

Earlier this year the troubled star was charged with cannabis possession after being found slumped at the wheel of his car in Hyde Park.

In a separate incident, he was questioned by police after colliding with three parked cars and driving off without informing their owners.

Last weekend, the News of the World caught the 43-year-old singer returning to his car after an encounter with 58-year-old Norman Kirtland on Hampstead Heath.

Police say they are not planning to investigate as no complaint had been made and the incident was not witnessed by an officer.

The singer has insisted in the past that he and Goss, 48, have an open relationship, saying: 'Gay relationships are a bit different. I'm sure we'll be allowed to roam if we want to. But we love each other dearly.'

Only three months ago Michael told Michael Parkinson that he was to seal his relationship, saying: 'We'll do it on our tenth anniversary, we'll probably do the formal legal thing then the party.'

But the source close to Michael yesterday admitted: 'They do not feel that it is relevant now.'