The government will legalise gay marriage, in spite of vocal opposition from Christian movements, Equalities Minister Lynne Featherstone has said as she prepared to publish details plans of the policy.
Ms Featherstone hit out at the "inflammatory" language used by senior religious figures and urged them not to "fan the flames of homophobia".
And she insisted that the consultation she will launch today will invite comments only on the practical implementation of marriages for same-sex couples by 2015 and not on the policy itself.
"There is no rolling back whatsoever. The essential question is not whether we are going to introduce same-sex civil marriage but how," she told The Independent.
Ms Featherstone appealed for calm in the mounting storm over the move - which has been forcefully championed by Prime Minister David Cameron in the teeth of significant Conservative opposition.
Half the party's supporters are against the change, a recent poll suggested, though it was backed by a margin of 45% to 36% among the wider public.
Cabinet Office minister Francis Maude, a leading Tory moderniser, warned recently that the party would be "unelectable" if it stuck to "backwards-looking social attitudes".
Tensions have been rising over the controversial issue since Britain's most senior Catholic, Cardinal Keith O'Brien, branded the proposal a "grotesque subversion of a universally acknowledged human right".
A letter from two senior Catholic archbishops was read out in 2,500 parishes on Sunday, urging congregations to "do all we can to ensure that the true meaning of marriage is not lost for future generations".
A campaign group, The Coalition for Marriage - C4M, has placed adverts in two national newspapers to coincide with the launch of the consultation which call the proposals "profoundly undemocratic".
Ms Featherstone said the strongly worded attacks "add nothing to the debate" and appealed for a common approach.
"We have a responsibility in leadership positions to make sure we don't fan the flames of homophobia.
"I totally respect all of the religious views and understand they are strong and genuinely felt. But to use such inflammatory language does not help the debate and does not help their cause," she told the newspaper.
"I don't want to see any polarisation between religious beliefs and gay rights. It is not a competition."
She suggested churches were attacking the policy in a bid to see off pressure within their congregations to extend religious ceremonies to gay couples despite Government assurances they would not be forced to host ceremonies.
"It is not legal and it will remain not legal to marry people of the same sex on religious premises," she said.
And she rejected a claim by the Archbishop of York, John Sentamu, that marriage law changes required the approval of the Church of England's General Synod.
"My understanding is that Parliament can legislate to do what it wishes," she said.
The Minister said same-sex marriage was "a very logical and very progressive step.
"It is illogical to say we have equality before the law but you can't have a civil marriage because you are gay."
But she conceded that it would do little to change the legal rights gay couples already enjoy through civil partnerships.