Actor Christopher Reeve, along with a group of scientific researchers, has filed a federal lawsuit against the Bush administration, accusing it of illegally withholding funding for stem cell research.
The suit claims the administration is doing "irreparable harm" by delaying the development of therapies that could save lives.
The Bush administration halted all funding and ordered a review of stem cell research soon after taking office. It now has less than 60 days to respond to the lawsuit.
"We are not suggesting that the administration should begin funding projects immediately," plaintiffs' attorney Jeffrey Martin said Tuesday. "We just want the process to move forward quickly, and with consideration of existing laws. We do not want delay because of politics."
Reeve, who played Superman in four movies, has been a prominent advocate of stem cell research since a horse-riding accident left him paralyzed.
The lawsuit, filed earlier this month in Washington, claims that Bush officials have skipped over administrative procedures necessary to halt research that federal statutes have made legal.
Last year, the National Institutes of Health passed guidelines that allow federal funding of some research involving stem cells, which many scientists believe have the potential to help repair injured or deteriorating organs.
The issue of federal funding for the research is especially sensitive because it sometimes involves experimentation with embryonic stem cells.
Those cells are derived from leftover embryos destined to be discarded after test-tube fertilization. Some ethicists and abortion opponents say it is wrong to use them for research, because it could encourage the creation of embryos for science.
Stem cell experiments on animals have shown promising results, but there is no conclusive evidence of the potential benefits of stem cell therapies on humans.
The lawsuit makes bold claims that, by delaying stem cell research, the Bush administration is "preventing or delaying the advent of a cure for paralysis, Parkinson's Disease, diabetes and other debilitating conditions."
"There is, in essence, a moratorium that is delaying the funding," Martin said.
In one of his first actions as president, Bush asked U.S. Department of Health and Human Sciences Secretary Tommy Thompson to review the guidelines of funding for stem cell research. That process includes the creation of a review board, which, as of late last week, has never met.
The lawsuit could force health officials to explain where they are in the review process.
"This is great because it will hopefully embarrass the Bush administration into action," said researcher Tim Dale of the Malen Clinic in New York. "At the very least it will make them explain themselves."
Among the plaintiffs are James Thompson of the Wisconsin Regional Primate Research Center, Roger Pedersen of the University of California, John Gearhart of Johns Hopkins University, Douglas Melton of Harvard University, Dan Kaufman of the University of Wisconsin, and Alan Osborne Trounson and Martin Pera, both of Monash Medical Centre in Australia.
— The Associated Press contributed to this report