Gay partners hoping for the same legal rights as married couples are in danger of becoming casualties of the political battle over the future of foxhunting.
The Civil Partnership Bill - which is due to come before the Commons on Tuesday - has just five weeks to complete its legislative journey in the lower house, and go back for final approval from the House of Lords.
The Bill would give gays the right to inherit property from their former partners if they die without making a will, and would allow them to benefit from their former partners' pensions and life insurance policies.
It has already suffered one political ambush when it went before the House of Lords last summer. A group of peers including the former Tory party chairman Lord Tebbit and the Bishop of Winchester claimed that it would be unfair on close relatives who have lived together for years if they did not have the same rights as gay couples. Their amendment, passed by the House of Lords, will almost certainly be thrown out by the Commons.
Jacqui Smith, the deputy minister for women, said yesterday: "Civil partnership has always been about ensuring that the thousands of same-sex couples who share their lives, their homes, their finances and often the care of their children will have the opportunity to have their relationships recognised in law."
But she added: "The amendments passed in the House of Lords would wreck the ability to put right this inequality. That is why we are determined to return the Bill to the original purpose supported by so many in the consultation." The legislation now has to be pushed through at the same time that the Commons and the Lords are locked in confrontation over the future of foxhunting. Peers are expected to spend about six full days arguing over the subject before they vote to overturn the proposed ban on hunting. The Bill will go back and forth, until the Commons invoke the Parliament Act to over-rule the peers.
Lord Lester, the Liberal Democrat peer and prominent civil rights lawyer, said: "I can't imagine the Tories starting a further battle to wreck the Bill, but with the Tories in their present state, anything is possible."
One leading Tory in the Lords denied that they wanted to stop the Bill going through, since it has the personal backing of the party leader, Michael Howard, but said it would be the Government's fault if it was blocked because they set the parliamentary timetable.
Peter Tatchell, the gay rights activist, also blamed government business managers for letting the Lords debate the Bill before it had been to the Commons.
"It was a major blunder for the Government to introduce the Bill in the Lords. This means Labour can't use the Parliament Act if a majority of peers block the legislation. Given that peers want to make life as difficult as possible for the Government over hunting, this Bill will probably be the casualty."
The Bill has come under fire from religious groups, who fear that it is a step towards giving legal recognition to gay marriages. But gay rights groups say that it does not go far enough, and that gay couples should have exactly the same rights in law as heterosexual couples. The Green Party is the only party to call for full legal recognition of gay marriages.