The mayor of London, Boris Johnson, has blocked plans for a Christian campaign group to post adverts on the capital's buses which claim that homosexuality can be cured.
Johnson pulled the campaign just days before the ads were due appear following complaints that they were homophobic.
The adverts from the Christian group Core Issues Trust mimics existing adverts from pro-gay group Stonewall and state: "Not gay! Ex-gay, post-gay and proud. Get over it!"
The campaign was also backed by Anglican Mainstream, a worldwide orthodox Anglican group whose supporters have equated homosexuality with alcoholism.
Core Issues Trust accused Transport for London (TfL) of censorship. TfL tweeted that the adverts did not reflect the capital's "tolerant and inclusive" ethos.
The adverts were reportedly booked for two weeks and due to appear on five bus routes in the capital, including top tourist destinations such as St Paul's Cathedral, Oxford Street, Trafalgar Square and Piccadilly Circus.
The adverts caused an uproar when they were revealed and forced Johnson to pull the plug on the campaign within two hours of the plans becoming public.
Johnson told the Guardian: "It is clearly offensive to suggest that being gay is an illness that someone recovers from and I am not prepared to have that suggestion driven around London on our buses."
Gay rights group Stonewall's spokesman Andy Wasley said: "We are delighted by TfL's clear commitment to diversity. It is fantastic that no adverts will be promoting voodoo, gay-cure therapy in London."
Core Issues' co-director Mike Davidson criticised the decision to axe the adverts. "I didn't realise censorship was in place," he told the Press Association
"We went through the correct channels and we were encouraged by the bus company to go through their procedures. They okayed it and now it has been pulled. I would be interested to know on what basis they have done that."
The campaign was launched in response to Stonewall's own promotion, which is visible on London buses, that says: "Some people are gay. Get over it."
Davidson said: "Their campaign rides roughshod over individuals who by conscience reject the simplistic notion that their choice to move out of homosexuality is because of internalised prejudice taught by society, completely ignoring the profound effect on sexual identity, established by highly respected scientific study, of childhood experience."