Bush threatens veto on stem cell research bill
(CNN) -- President Bush on Friday threatened to veto a bill expanding public funding for embryonic stem cell research that could make it to his desk by early next week.
"I made [it] very clear to the Congress that the use of federal money, taxpayers' money, to promote science which destroys life in order to save life, I'm against that," Bush told reporters. "Therefore if the bill does that, I will veto it."
It would mark the first veto of Bush's presidency.
Supporters of the bill dispute Bush's depiction of the research, saying it's critical to advance scientific discoveries that may help cure diseases.
The bill would broaden the limits on funding embryonic stem cell research beyond the strict rules the president outlined four years ago.
Bush limited funding for research on human embryonic stem cells to cell lines already in existence at that time.
Bush aides have said they're concerned the measure still may pass the GOP-led Congress by a veto-proof margin. They're working to convince enough Republicans to support the president.
In the House of Representatives, 290 votes are needed to override a veto.
Republican congressional leaders have told GOP lawmakers to consider the legislation a "vote of conscience" -- meaning they are not pressuring members to vote any particular way.
The House could take action next week on the legislation.
The bill -- backed by Reps. Mike Castle, R-Delaware, and Diana DeGette, D-Colorado -- would lift that restriction. The bill has about 200 co-sponsors.
The scientific community complains many of those stem cell lines are contaminated and could not be used for research. A study published in January in the journal Nature Medicine said all those lines are contaminated.
Some Republicans have called on the president to alter his stance, including former first lady Nancy Reagan. Her husband's long battle with Alzheimer's disease helped draw attention to the issue.
The disagreement highlights a fissure in the Republican Party, with Bush siding with the Catholic Church and social conservatives against the GOP's more moderate voices.
White House officials said they may try to recruit first lady Laura Bush as a spokeswoman. Mrs. Bush, the daughter of an Alzheimer's sufferer, spoke out on the matter during the 2004 re-election campaign.
Officials said the administration will stress that the president is not opposed to stem cell research but remains concerned about how how taxpayer dollars are spent.
Officials said the administration also is considering stepping up focus on less controversial stem cell research, such as that focusing on blood from umbilical cords of newborns.
President Bush said Friday he is a "strong supporter of adult stem cell research."
CNN's Dana Bash and Ed Henry contributed to this report.