The U-S House of Representatives Tuesday voted 265-162 to ban all human cloning, including cloning for reproduction or medical research.
The bill passed by the Republican-led House would impose a 10-year prison sentence and a $1 million fine for any attempt at human cloning.
The measure awaits Senate action, and President Bush has said he supports the ban.
The House vote came after an emotional debate on the ethical and scientific implications of cloning.
While lawmakers all agreed with the idea that humans should not be cloned, they disagreed over whether scientists should be able to clone human embryos for use in finding cures for diseases.
Some quoted scientists who say that embryonic stem cells have the potential for alleviating serious ailments.
Louise Slaughter is a Democrat from New York who opposed the ban. "If we stifle our nation's research efforts, patients will suffer. This research holds the potential to treat diseases of millions of Americans, including diabetes, cancer, heart disease, stroke, Parkinson's, Alzheimer's, brain or spinal cord injury or multiple schlerosis," she said.
But many anti-abortion advocates, like House majority Whip Tom Delay, oppose the use of such stem cells in medical research. "This exploitive unholy technique," he said, "is no better than medical strip mining. The preservation of life is what is being lost here."
President Bush is considering whether to allow federal funding for medical research using stem cells from human embryos.