Amnesty International risks alienating some of its high-profile rock star backers in the row over its decision to support women’s access to abortion.

The group has been accused of “duping” the singers Christina Aguilera and Avril Lavigne, who have both made statements against abortion and are among contributors to an Amnesty CD released to raise money for survivors of the atrocities in Darfur.

Two weeks ago, just two months after the album’s release, Amnesty adopted a worldwide policy to back the right of women to abortion in carefully defined circumstances — for example, when their health or life are in danger or when they have been victims of rape in areas of conflict such as Darfur.

The album, which has already sold more than 400,000 copies, features cover versions of hits by John Lennon such as Imagine, and Give Peace a Chance. It was made possible by Lennon’s widow Yoko Ono, who gave the rights to all his solo works to Amnesty in 2003.

The policy on abortion has brought Amnesty into conflict with the Roman Catholic Church, and has shown how new divides have displaced the old left-right geopolitics that gave rise to Amnesty. The group was founded in Britain in 1961 by Peter Benenson, a radical socialist lawyer and a Catholic convert, to campaign for the release of prisoners of conscience.

Now Rock for Life, a collaboration of musicians linked to the antiabortion movement, has accused Amnesty of using the album to promote abortion without making its intentions clear to the singers.

Erik Whittington, director of Rock for Life, said: “The human suffering going on right now in Darfur is horrific. To add insult to injury, however, using this tragic abuse of human rights to raise money for a pro-abortion organisation is hypocritical and beyond belief.

“The manipulation of musicians to fund this hypocrisy is maddening.” He added: “We are writing to all the artists to ask for their views.”

Amnesty, which claims 260,000 members in Britain, more than the Labour party, has been surprised by the ferocity of the reaction to its new policy.

The position has been condemned as support for a “right to kill” never envisaged in the United Nations 1948 declaration of human rights that formed the original bedrock of Amnesty’s focus. The Vatican has called on Catholics to withhold donations and Amnesty’s Irish section has said it will effectively opt out of the policy and not participate in abortion-related campaigns.

Last week Michael Evans, the Catholic bishop of East Anglia, resigned from Amnesty after 31 years as an activist saying it had been “deeply compromised”. Many Christians among Amnesty’s 2m members worldwide are said to be considering following suit, although Amnesty officials in London insisted only “a handful” had done so.

The views of singers who have contributed to the album - who also include George Harrison’s son Dhani - on Amnesty’s change of heart are not yet clear.

But Aguilera, 26, is a devout American Catholic. She is reportedly expecting her first child and has taken part in a television show in which she interviewed a teenager who had kept her baby rather than have an abortion.

Lavigne, 22, is a French-Canadian from a tight-knit Christian family. Her song Keep Holding On is the backing track to a pro-life video on YouTube that declares “abortion is murder”.

Aguilera and Lavigne were unavailable for comment. An aide to Lavigne said: “I don’t think she would want to comment on this. But what has abortion to do with Amnesty? It’s for a lot of different things such as prisoners of conscience and human rights.”

Rock for Life has drawn up a list of 700 acts, including Bryan Ferry and the rapper MC Hammer, who it says are opposed to abortion.

An Amnesty spokesman said: “We don’t know the personal opinion of the artists on abortion but the CD has been launched to raise awareness of the situation in Darfur.”

Widney Brown, Amnesty’s director of policy, said there had been “overwhelming support” for the policy change at the meeting in Mexico City. Since 2005 72 branches of Amnesty around the world have passed similar motions.

Amnesty’s position now is not for abortion to be a universal right but for it to be decriminalised and for access to abortion to be permitted within its defined circumstances.

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