The Conservatives will consider the case for legalising same-sex marriages, but gay rights campaigners remain sceptical.
Yesterday a protest outside Tory party headquarters in central London took place to put pressure David Cameron's party, after shadow home secretary Chris Grayling backed bed-and-breakfast owners who would not accept gay couples.
Shadow chancellor George Osborne told Mr Tatchell in a meeting yesterday that he and Mr Cameron were happy to reassess gay marriage, which would go beyond the current civil partnerships arrangement.
As this would not necessarily involve a review of the law, Mr Tatchell has condemned the pledge as "meaningless".
"Civil partnerships are not good enough," he added.
"The Conservatives are out of step with popular opinion. The British public now believe that the law on civil marriage should not discriminate."
A Populus poll for the Times last June found more than six out of ten people think lesbian and gay couples should be allowed to marry in a registry office in the same way as heterosexual ones.
The Conservatives have announced two specific gay rights policies in recent days.
David Cameron has pledged to adopt a zero tolerance approach to homophobic bullying in schools.
And any convictions for consenting gay behaviour that have since become lawful will be deemed as spent - meaning they will be wiped from the offender's criminal record.