THE Tory leader defended himself against fresh criticism from Conservative MPs yesterday, this time over his decision to order them to vote tonight against legislation that would allow unmarried and gay couples to adopt.

Iain Duncan Smith denied that the move to impose a three-line whip on the Adoption and Children Bill would undermine his latest attempt to portray the Conservatives as an inclusive modern party.

But, in an obvious attempt to reduce the impact of a certain revolt, he made it plain that no disciplinary action would be taken against those defying the whip.

Members of the Shadow Cabinet who oppose the leadership line, such as Tim Yeo and John Bercow, are expected to find reasons to miss the vote. The latest headache for Mr Duncan Smith came as he acknowledged that there were people trying to undermine his leadership.

Interviewed on the Jonathan Dimbleby programme on ITV 1 he said: “There are a few people who have decided that they wanted things changed or different but that’s not going to happen.”

He said: “My party has full confidence in me for one major reason. I was elected by the membership of this party, not just MPs – and I was elected on a basis absolutely to go ahead and take this party back to electability, and I have absolutely no interest in one or two people who may have a different agenda.”

Yesterday several MPs openly criticised his decision to impose a whip over adoption. Andrew Mackay, a former Shadow Cabinet member, said it was “difficult to explain or understand why we are doing it”. He added: “I think the State or political parties telling people how to behave is something fairly abhorrent which normally only happens under fairly restrictive regimes.”

Andrew Lansley, another former frontbencher, said that the attempt to resist adoption by unmarried couples would be seen as poor.

But their leader rejected claims that the move was at odds with his efforts to rid the Conservatives of their old “nasty party” image.

“I don’t think that it is about being nice. I don’t think it is about being modern or old-fashioned,” he said. “It is about children in need, children in care, not lifestyle choices. As far as I am concerned, children come first, lifestyle choices then come second.”

He said that if heterosexual couples really wanted to adopt, they should get married. “For unmarried couples there has always been the prospect of adopting. If they want to adopt and are serious about it, getting married is always the option,” he said.

Disclosing his soft line on the vote he added: “I don’t think people spend time saying, ‘Hang on a second what if two or three people aren’t there, are they away on a trip, are they visiting somewhere, are they there to vote?’.”

Meanwhile David Davis, who is seen as a certain future contender for the leadership, said he was “as certain as it is possible to be” that Mr Duncan Smith would lead the Conservative Party into the next general election.

He refused to rule himself out as a contender if party discontent eventually forced the leader from office but said speculation over internal discontent was damaging. He told the BBC’s On The Record: “What concerns me is that if we carry on doing this, and undermining leaders, we are never going to get anywhere.

“The people doing the briefing are doing harm to the party — there’s no doubt about that. They are making Iain’s job incredibly difficult. I’m as certain as I can be – subject to strikes by lightning – that he will make it to the next election, lead us into the next election.”

Mr Davis also defended Mr Duncan Smith over adoption. Politicians had a “moral responsibility” to protect extremely vulnerable children and the public would not see the Tory position as illiberal, he said.

He said he fully expected some MPs would ignore the three-line whip, saying it was “pretty loose”.

The former Tory Party chairman Lord Tebbit attacked likely rebels over adoption, saying they had “got the issue wrong”.

“You go down to the pub and you say to people, ‘Do you think that homosexual couples should be allowed to adopt children?’ I can tell you the answer now,” he said.

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