The mystery surrounding the identity of a smartly-dressed man found unconscious and freezing on a beach was solved yesteday after his fiancée stepped forward.

The man, who sparked a nationwide appeal for help in identifying him after he suffered memory loss, has been revealed to be a 26-year-old from London.

He was discovered by a passer-by unconscious and soaking wet on Brighton beach in East Sussex, between the Palace Pier and the Marina, on February 12. It is not known how long he had lain there for but he was suffering from hypothermia and was admitted to the city's Royal Sussex County Hospital.

Sussex Police said his fiancée saw newspaper reports about his plight and travelled from the capital to Brighton yesterday to identify him.

A police spokesman said: "Having made inquiries and considered all the circumstances we are satisfied that this is so."

His family have been informed but neither they nor the man have given authority for his identity to be publicly released, police said.

Inspector Roy Apps, who led the inquiry, said: "We are grateful to the media for the publicity which has resulted in our solving this mystery."

The man remains in hospital while doctors consider whether he needs any further treatment. Earlier, police said he was in a "fragile state" but was making a good physical recovery.

Mr Apps said: "In two weeks he has made a remarkable recovery in hospital, but he is in a fragile state and is therefore being treated as a vulnerable person.

"He has a happy, positive, cheerful personality and has been very helpful to us in trying to establish his identity. We believe that this is a genuine case of memory loss."

He speaks good English without any apparent accent, and appears to have some general knowledge of south-east England. Mr Apps added: "We have taken him out and about in Brighton and Hove in a bid to jog his memory and, while he appears to show some recognition, we are not sure that this is the case.

"When introduced to police officers and nurses he has sometimes assumed that their names are his own."

The case has drawn comparisons to the discovery of a man, dubbed the Piano Man, in Kent in 2005.