The Tory party and Labour have become locked in a battle as to who is the more gay friendly party as they vie to win over the UK's three million pink voters.
The war of words escalated ahead of the Gay Pride march in London today after a Cabinet minister accused the Tories of being 'plagued by homophobia'.
Culture Secretary Ben Bradshaw claimed last night that many Conservative MPs were prejudiced against people in same- sex relationships.
Mr Bradshaw, one of the first MPs to enter into a civil partnership, spoke out ahead of the Gay Pride march in London today, as a poll suggested that increased numbers of the UK's three million 'pink voters' were turning to the Tories.
Row: Ben Bradshaw claimed some Tory MPs were still homophobic, but Conservative MP Alan Duncan has accused Labour of 'stirring up hatred'
'A deep strain of homophobia still exists on the Conservative benches,' he claimed, adding that David Cameron 'talks the talk but doesn't walk the walk' on the issue.
Foreign Office minister Chris Bryant, who is openly gay, said: 'I think if gays vote Tory, they will rue the day very soon.
'I don't think David Cameron is homophobic personally, but I don't trust him on these issues,' he added.
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But Shadow Leader of the Commons Alan Duncan accused his Labour counterparts of 'stirring up hatred' and using 'desperate' tactics to shore up flagging support.
He said: 'This is the last gasp of Labour's desperation.
'Bradshaw and Bryant are simply trying to stir up hatred and division from the last century and it's both unwarranted and unworthy. It's simply untrue.
Civil partnerships are allowed in Britain, but campaigners say neither Tories nor Labour support full gay marriage
'I believed we had reached the happy point where politics had been taken out of this altogether. But these remarks show that Labour is actually the nasty party.'
Mr Duncan is one of two gay Shadow Cabinet ministers, along with Nick Herbert.
A poll by Jake, a networking organisation for homosexual professionals, found 38 per cent of its members would vote Tory at the next election.
Apology: David Cameron and George Osborne leave the gay pride fundraiser last week where the Tory leader spoke
Labour came behind the Liberal Democrats on 20 per cent, even though 86.6 per cent of those surveyed admitted it was the party that had achieved the most for gay people.
Gordon Brown is due to greet organisers at a reception at No. 10 this morning, while his wife Sarah is expected to join the one million lesbian, gay, bisexual and transgender marchers at the rally in London later today.
This week Mr Cameron apologised for his party's backing of Section 28 in 1988 - a controversial law banning local authorities from portraying homosexuality in a positive light.
The first Tory leader to speak at a gay pride event, Mr Cameron said: 'I am sorry for Section 28. We got it wrong. It was an emotional issue. I hope you can forgive us.'
Ben Summerskill, chief executive of gay rights campaign Stonewall, described the apology as 'historic', adding that it would remove a major obstacle in the way of many of Britain's three million gay people voting Tory.
Harriet Harman, the Leader of the Commons, said that David Cameron’s apology was 25 years too late.
Labour MP Chris Smith was the first to come out publicly in 1984. Currently 11 MPs are openly gay - a figure that is expected to rise after the next election.