KEY POINTS:
WASHINGTON - President George W Bush has vetoed legislation to expand federally funded embryonic stem cell research, triggering an uphill battle to override him in the Democratic-led US Congress and likely pushing the issue onto the 2008 election agenda.
Two-thirds majority votes would be needed in the Senate and House of Representatives to overcome Bush's opposition and make the bill law. Backers admitted they are short of support. A few dozen of Bush's Republicans in Congress back the measure.
The president and other critics condemn the legislation as morally offensive because it would lead to the destruction of human embryos to derive stem cells.
But backers note the legislation would only permit scientists to use embryos left over from fertility treatments that would otherwise be discarded. They also say it could clear the way for possible medical advances that could help millions of people suffering with debilitating diseases.
"If this legislation became law, it would compel American taxpayers for the first time in our history to support the deliberate destruction of human embryos," Bush said. "I will not allow our nation to cross this moral line."
In addition to vetoing such legislation for the second time in two years, Bush issued an executive order to encourage scientists to work with the federal government to derive new methods to obtain stem cells without harming human embryos. He announced no new funding, however.
Critics called his order a sham and said Bush should have signed into law the stem-cell bill, which polls show is backed by more than 60 percent of American voters.
"Once again, the president has ignored the will of the American people, of leading medical researchers, and of a bipartisan majority of the Congress," said House Speaker Nancy Pelosi, a California Democrat.
"I believe history will not look kindly on the president's actions," said Rep Christopher Shays, a moderate Connecticut Republican.
But Republican Sen George Voinovich of Ohio backed Bush, saying: "We can and must find cutting-edge techniques to cure disease and ease suffering without destroying life. The president today stood on the side of life."
Shortly after Bush took office in 2001, he allowed federal funding on 78 stem cell lines then in existence. Most turned out to be of limited use to scientists, who have urged the president to lift his restrictions.
Democrats promised to push to expand stem cell research in winning control of Congress last year, and it appeared certain to be an issue again next year when US voters elect a new Congress and president.
Embryonic stem cells are the source of every cell, tissue and organ in the body. Scientists study them to understand the biology not only of disease, but of life itself, and want to use them to transform medicine and find cures for such debilitating illness as Parkinson's, cancer and diabetes.
Bush noted that scientists this month reported that in tests with mice they had made progress on alternative ways to produce stem cells without destroying embryos -- a breakthrough, which if it works in humans, could ease ethical concerns.
But those scientists cautioned there was no guarantee of quick success with human cells, and urged passage of the bill.
Democrats said they were just one vote short in the Senate of being able to get a two-thirds majority to override Bush's veto, but would have to pickup dozens of additional votes in the House to obtain support needed to prevail. The White House said it was confident Congress would sustain the veto.
- REUTERS