Beleaguered British Prime Minister Gordon Brown avoided a major rebellion as legislation to regulate the use of human embryos for research passed its first parliamentary hurdle late Monday.
Just nine lawmakers from the governing Labour party voted against the bill, which was passed for a second reading by 340 votes to 78, a majority of 262.
The Human Fertilisation and Embryology Bill would allow the creation of hybrid human and animal "admixed" embryos, which scientists hope will lead to advances in the treatment of debilitating conditions such as Alzheimer's and Parkinson's.
But the government will face a sterner test when the measures are scrutinised again next week and Labour lawmakers have a free vote on some of its most contentious elements, a measure granted by the government to appease Catholic lawmakers.
They include the creation of hybrid embryos, or so-called "saviour siblings" which allow a brother or sister to help a sibling to recover from disease.
Health minister Alan Johnson said research would only be carried out under a "strict legal and ethical framework."
Campaigners against the bill vowed to keep fighting.
Ann Widdecombe of the main opposition Conservatives said: "Clearly there is all to play for, with the large number of MPs abstaining indicating that many have still to make up their minds."
The leader of Catholics in Scotland, Cardinal Keith O'Brien, has described the bill as a "monstrous attack on human rights, human dignity and human life."
Brown is under fire from his own party after a disastrous showing in local elections earlier this month.
Former welfare reform minister Frank Field said Sunday he would be "very surprised" if Brown were still in charge when Britain next goes to the polls, but the prime minister's spokesman insisted he would not be ousted before the next general election.