The White House says President Bush will veto a bill later Wednesday that would expand government funding for embryonic stem cell research - despite strong bipartisan support for the bill in Congress.
The U.S. Senate passed the measure by a vote of 63 to 37 on Tuesday. It would allow federal funding for research on embryos derived from fertility treatments that would otherwise be discarded. The House of Representatives passed the bill last year.
Supporters say embryonic stem cell research could aid in the treatment of Parkinson's disease, diabetes and spinal cord injuries.
But President Bush opposes it on the grounds that it kills a potential human life. A White House spokesman said today there is a "moral line" the president will not cross.
The veto will be the first of Mr. Bush's presidency.
Neither the House nor the Senate appear to have the necessary two-thirds majority needed to override a presidential veto. Tuesday's vote in the Senate fell just four votes short of the 67 needed to overturn a veto. Nineteen Republicans joined all but one Democrat in backing the bill.
Public opinion polls show a large majority of Americans support embryonic stem cell research. Campaigners for such research include Nancy Reagan, the widow of former President Ronald Reagan. He died after a long battle with Alzheimer's disease.
The Senate also passed two less-controversial bills Tuesday. One would prevent production of embryos solely for stem cell harvest. Another would encourage research alternatives that do not destroy embryos.
Mr. Bush is to make remarks later Wednesday to an audience that includes parents of children adopted as embryos.
Some information for this report was provided by AFP, AP and Reuters.