A furious political row over homophobia intensified last night when the Conservatives accused two openly gay ministers of “stirring up hatred and division” after they claimed that many Tory MPs were homophobic.

As up to a million people prepared for the Gay Pride march in London today, Ben Bradshaw, the Culture Secretary, sparked outrage by declaring that “a deep strain of homophobia still exists on the Conservative benches”. Chris Bryant, the Foreign Office minister, added: “If gays vote Tory, they will rue the day very soon.”

Harriet Harman, the Leader of the Commons, also weighed in, saying that David Cameron’s apology this week for the Conservative attitude on Section 28 was 25 years too late.

Alan Duncan, one of two gay Shadow Cabinet ministers, accused Mr Bryant and Mr Bradshaw of “stirring up hatred and division”.

He said: “I have publicly paid tribute to Tony Blair for his achievements, particularly on introducing civil partnerships. David Cameron this week said that on Section 28 we had to admit we got it wrong. The party has changed. I bet in Labour backwaters there are plenty of people who don’t like the fact that Ben Bradshaw is gay.”

The Conservatives are keen to stress that their prospective election candidates include a number of gay people, including the party’s vice-chairman, Margot James, and that the next generation of Tory MPs will be more socially liberal. In a survey of 144 prospective parliamentary candidates in winnable seats for the ConservativeHome website, 62 per cent said that same-sex couples should be given the same benefits as married couples, while 31 per cent disagreed.

Mr Cameron apologised this week for Section 28, the controversial law brought in by the Conservatives in 1988 banning local authorities from portraying homosexuality in a positive light. Mr Cameron, the first Tory leader to speak at a Gay Pride event, said: “I am sorry for Section 28. We got it wrong. It was an emotional issue. I hope you can forgive us.”

His words were described as historic by Ben Summerskill, the chief executive of Stonewall, the gay rights group, who added that the apology removed a major obstacle that had stopped many gay people voting Tory. However, Mr Bradshaw and Mr Bryant urged gay people to study Conservative voting records on issues such as gay adoption and hate crimes. Ms Harman, whose Equalities Bill would outlaw discrimination on the ground of sexuality, urged people to disregard Mr Cameron’s words.

She told Pink News: “I don’t think anyone should be fooled by the apology, which is already 25 years too late. It is not the view of the Tory party. They have voted against the Equality Bill. If they were sincere, they would support it.”

A survey by Jake, a networking group for gay professionals, found that 38 per cent of gay people questioned would vote Conservative, even though just 4 per cent said that the Tories were gay-friendly.

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