Read the text of the letter from the Archbishop to The Times

Britain’s leading Roman Catholic churchman gives warning today that the role of a father in a child’s life will be undermined by legislation to make it easier for lesbian couples to become parents to test-tube babies.

Cardinal Cormac Murphy-O’Connor expresses in a letter to The Times his strong opposition to the proposal, which is being debated in the House of Lords today.

Opponents of the move, which will grant gay couples the same parenting rights as heterosexuals, say it will “drive the last nail in the coffin of the traditional family”.

The Archbishop of Westminster’s intervention is the culmination of a campaign by Conservative and Labour politicians to defeat a law that will allow lesbian couples to become parents to test-tube babies without fathers having any further role in their lives after donating sperm.

In his letter Cardinal Murphy-O’Connor says that it is “profoundly wrong” and subordinates the rights of the child to the desire of the women.

He writes: “The Bill proposes to remove the need for IVF providers to take into account the child’s need for a father when considering an IVF application, and to confer legal parenthood on people who have no biological relationship to a child born as a result of IVF. This radically undermines the place of the father in a child’s life, and makes the natural rights of the child subordinate to the desires of the couple. It is profoundly wrong.”

He calls on Gordon Brown to follow the example of the opposition parties and allow Labour members of both Houses of Parliament a free vote on the Human Fertilisation and Embryology Bill.

The Bill would remove the requirement on test-tube clinics to ensure that a father is involved in the upbringing of any child that he helps to create.

Campaigners against the proposal insist that the existing requirement amounts to legal recognition that every child has the right to a have a father. The campaign is being led by Iain Duncan Smith, the former Conservative Party leader, who said the proposal would “drive the last nail in the coffin of the traditional family”.

He added that the Government’s move came just as society was starting to appreciate the vital role fathers played in the successful upbringing of children. “Labour ministers are sending out the utterly wrong signal that fathers don’t matter,” he said.

Forty-five Labour MPs have signed a Commons motion saying that the plans are “profoundly misinformed and clearly undermine the best interests of the child”. But supporters of the measure attacked opposition to the Bill. Evan Harris, the Liberal Democrat science spokesman, said: “The research evidence is clear that children do well in lesbian households and when brought up by mature solo women who plan their motherhood, so imposing a requirement on clinics to consider the need for a father in such cases is both unjustified and unlawful discrimination.”

He added: “The Conservatives’ bizarre wish to impose fathers on lesbian households suggests that some Tories simply don’t understand anything beyond their own traditional backgrounds.”

Ben Summerskill, chief executive of Stonewall, the gay rights group, said that the Bill would merely extend the right already available to heterosexuals. “At a time when three million children in this country are growing up in single-parent households, it seems odd there should be this obsession with a few hundred who have an opportunity to have a second loving parent,” he added.

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