David Davis, the shadow home secretary, has come out in support of the Roman Catholic Church in the gay adoption row, after Cardinal Cormac Murphy-O'Connor said last week that it would be unjust if new sexual orientation laws forced the Catholic Church's adoption agencies to place children with gay couples.

Leader of the Conservatives, David Cameron, has yet to break his silence on the gay adoption issue, which also brought forth a joint statement from the Archbishops of Canterbury and York last week in which they gave their support to the Catholic Church.

Mr Davis said he would oppose new regulations that would make it illegal for Catholic adoption agencies to turn away gay couples, The Telegraph reported.

Tory right-wingers backed his intervention, as they appealed to the party leader to voice his support on freedom of conscience.

Prime Minister Tony Blair withdrew his support for the gay adoption opt-out on Wednesday under pressure from backbenchers and senior ministers. The best compromise Mr Blair could manage was a one year "transitional period" to allow Catholic adoption agencies to adapt to the new law.

Speaking on BBC1's Sunday AM, Mr Davis revealed his intention to vote against the measure when it comes to the Commons next month.

"I will almost certainly vote against this measure because, because I think there's a better compromise available," he said.

Mr Davis, who founded the Conservative Adoption Forum, said in The Telegraph report he wanted to defend the "very proper right of children to have the best available adoption service.

"These are very, very badly damaged children and actually the Catholic Adoption Society is the best to deal with that.

"If the consequence of this is actually 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 do something else or find a better compromise."

Meanwhile, Ann Widdecombe, the former Home Office minister, said she was not surprised that Mr Cameron had not intervened in the debate so far but added: "I would hope that he will come out in favour of freedom of conscience.

"It's one thing to say that gay people can adopt and quite another to say they must be able to adopt from a specific agency. It's like saying someone not only has the right to have an abortion but they also have the right to demand an abortion from a specific doctor, regardless of that doctor's freedom of conscience."

Edward Leigh, the Tory chairman of the Public Accounts Committee, added: "This is an almost fascistic measure. No-one is forced to go to a Catholic adoption agency yet ministers are trying to force these agencies to abandon their deeply-held beliefs and subscribe to the liberal orthodoxy. I would hope and expect our leader to speak out in favour of freedom."

According to Conservative insiders, Mr Cameron has adopted a "wait and see" approach to the issue ahead of the free vote in the Commons next month.