Conservative MPs demanded an apology today from Labour's candidate for London mayor, Ken Livingstone, after an interview in which he said their party was "riddled" with homosexuals and claimed Baroness Thatcher was "clinically insane" while prime minister.
Mr Livingstone told the New Statesman that some Tory MPs were hypocritically denouncing homosexuality, while secretly "indulging".
But he said that by contrast, since the leadership of Tony Blair, being gay or lesbian had been a boon to Labour MPs' careers.
Discussing the issue of privacy with the magazine's associate editor Jemima Khan, Mr Livingstone said: "(The public) should be allowed to know everything, except the nature of private relationships - unless there is hypocrisy, like some Tory MP denouncing homosexuality while they are indulging in it."
Asked why he referred particularly to Conservative MPs, he added: "Well, the Labour ones have all come out. As soon as Blair got in, if you came out as lesbian or gay you immediately got a job. It was wonderful.
"You just knew the Tory party was riddled with it like everywhere else is."
Conservative London MPs Angie Bray and Mike Freer wrote to Labour leader Ed Miliband calling on him to ensure that the remarks were retracted.
Ms Bray said: "These are the sort of offensive remarks we hear all too often from Labour's candidate for mayor.
"Ed Miliband should condemn these outrageous comments and get him to apologise immediately."
A spokesperson for Ken Livingstone said: "Ken is clearly saying the advance of lesbian and gay people into politics is unequivocally a good thing.
"He has fought for equality for gay and lesbian people throughout his life, and the fact they are represented in all major political parties is a sign of the progress that has been made."
In a colourful interview, Mr Livingstone also branded the director general of the BBC Mark Thompson "a moral imbecile" for censoring the word Palestine in a song and described bankers' bonuses as being "like penis extensions".
He said that his rival in the May race for the mayoralty, Tory incumbent Boris Johnson, had "real ability, real intelligence", but would never achieve his potential because he did not take life seriously.
"It is why I think in the end he won't be prime minister," said Mr Livingstone.
"I don't think he has really got a solid ideological brain, like (Chancellor George) Osborne or (Foreign Secretary William) Hague.
"It is very hard to find anything in Boris's career that he's serious about. He just loves life too much to really succeed as a politician."
Mr Livingstone blamed his distinctive voice for his own failure to make it to 10 Downing Street, saying: "I would like to sound like James Mason.
"I reckon if I'd had a better voice I could have been prime minister. It is the most irritating voice in public life."
In a less controversial interview with the same magazine, Mr Johnson repeated his defence of high pay in the City, saying: "We are endlessly focused on the very narrow, newspaper-driven agenda of rage against anybody who creates wealth.
"That sort of hatred of bankers and bonuses - which I perfectly understand emotionally - is just the wrong target. What you need to do is focus on what these people could be doing to help those at the bottom."
Mr Johnson revealed that he is trying to learn Homer's Iliad by heart, but has so far consigned only the first 100 of more than 15,000 lines to memory.
He said his proudest boast was to have "delivered a sound, progressive administration of London over the last four years, which has cut tax and cut crime".
Mr Livingstone said that, if elected, he would restore 1,700 police jobs and cut public transport fares.