A body believed to be that of missing children's television presenter Mark Speight has been found in a remote area of a London railway station, police said on Sunday.

British Transport Police were called to Paddington Railway Station at 10am on Sunday following the discovery of the body.

The dead man was not struck by a train and the death is being treated as unexplained, British Transport Police said in a statement. The body had yet to be formally identified.

Police said on Tuesday that Speight, 42, had been reported missing two months after his fiancee's death.

He was last seen boarding a southbound Bakerloo line train from Queen's Park station on Monday.

Speight, who hosted the BBC art show SMart, was questioned by police over the death of his fiancee Natasha Collins, 31, at their St. John's Wood home in January.

Westminster Coroner Paul Knapman recorded a verdict of death by misadventure at an inquest last week. The court heard that Collins died in a scalding hot bath after taking cocaine and sleeping pills and drinking vodka.

Speight was briefly held on suspicion of her murder before detectives "cancelled" his arrest and said he was not a suspect.

A statement released by his lawyers at the time of Collins' death, said Speight was "absolutely distraught".