Government divisions over gay adoption spread to the Conservatives yesterday as a senior MP said Catholic agencies should not have to help gay couples adopt a child.
Shadow home secretary David Davis said he would "almost certainly vote against" the introduction of regulations prohibiting everyone providing goods and services from discriminating on the grounds of sexual orientation - including Catholic adoption firms.
His comments clash with David Cameron's vocal support for the rights of gay couples and for civil partnerships, but today the Tory leader played down the rift, saying he believed his party should have a free vote but noting he would vote against an exemption.
Tony Blair will announce details of the sexual orientation regulations this week, which are expected to reject the Catholic church's request for an exemption but instead offer a delay before they are introduced, to give agencies time to comply.
The move comes in the wake of intense lobbying by the church, which included the archbishop of Westminster, cardinal Cormac Murphy-O'Connor, writing to ministers warning the laws could see Catholic adoption agencies close across the country.
Yesterday Mr Davis told BBC One's Sunday AM warned these agencies, which make up a third of the voluntary adoption sector, must not be allowed to close and said he believed there was a "better compromise available" than the government's plans.
"If the consequence of this is actually that we end up with a worse adoption system then that's a reason to come back to this and say perhaps this is not the right answer, we should.find a better compromise," he said.
But he acknowledged it was a "challenge" to find a balance between the right of gay people not to be discriminated against and the right of children to have the "best available adoption service".
Speaking this morning, Mr Cameron said he would oppose any attempt to exempt Catholic adoption agencies, saying it would lead to "all sorts of other people wanting block exemptions from the law".
"If we're faced with a choice of saying look you can either have these regulations that ensure we don't discriminate against people on the basis of sexual orientation, or you can't have these regulations at all, which is the choice, I shall vote for the regulation, because I think it's right that we have in this country clear rules against discrimination," he told BBC Radio Four's Today.
But he added that MPs "really need to find a decent compromise because we want to keep the Catholic adoption agencies", and said giving them three or four extra years to work out solutions, such as twinning with adoption agencies, could work.
Mr Cameron also accused the prime minister - who is thought to be privately in favour of an exemption - of "mishandling" the issue.