A member of the U.S. Congress who co-sponsored a bill to expand stem-cell research funding has criticized President Bush for vetoing the measure.

Representative Diana DeGette said in a radio address Saturday that the United States has an ethical responsibility to help cure diseases that affect more than 10 million Americans and their families.

Supporters of stem-cell research include scientists and a number of prominent Republicans. They say the research could aid in the treatment of Parkinson's disease, diabetes and spinal cord injuries.

Mr. Bush has said he opposes expanding funding for stem-cell research because harvesting stem cells from a human embryo kills a potential human life.

But DeGette said today she believes Mr. Bush was motivated by political gain rather than morality when he vetoed the measure on Wednesday.

DeGette is a Democrat from the western U.S. state of Colorado. She predicted the issue will be a top priority in this year's November elections.

The bill that President Bush vetoed would allow federal funding for research on embryos derived from fertility treatments. Those embryos would otherwise be discarded.

The bill had a number of high-profile backers, including Senate Majority Leader and medical doctor Bill Frist, and former First Lady Nancy Reagan, whose husband Ronald Reagan died of Alzheimer's disease.

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 of the Senate's Democrats in backing the bill.

Some information for this report provided by AP.