Claims former prime minister Sir Edward Heath was gay but was told to keep his sexuality secret for the sake of his career have been dismissed.
Sir Edward was prime minister in the early 1970s
Tory London Assembly member Brian Coleman said Sir Edward was told in the 1950s "cottaging" - seeking gay sexual partners - could harm his career.
Writing on the New Statesman website, Mr Coleman said the warning had been "common knowledge" in the party.
But Tory MP Derek Conway said there was no evidence for the claims.
Sir Edward, who was prime minister from 1970 to 1974, never married and his sexuality has long been a subject of speculation.
Mr Coleman writes: "The late Ted Heath managed to obtain the highest office of state after he was supposedly advised to cease his cottaging activities in the fifties when he became a privy councillor."
Mr Coleman claimed that it was "common knowledge" among Tories that Sir Edward had received the warning.
But Mr Conway, who succeeded Sir Edward as Tory MP for Old Bexley and Sidcup in 2001, rejected the suggestion.
He said: "If there was some secret I'm sure it would have come out by now.
"Ted was absolutely wedded to politics. He didn't have a great deal of personal companionship in his life but there are people who are capable of getting on without companionship."
Sir Edward died, aged 89, in 2005.