WASHINGTON — From tiny embryonic cells to the large-scale physics of global warming, President Obama urged researchers yesterday to follow science and not ideology as he abolished contentious Bush-era restraints on stem-cell research.

"Our government has forced what I believe is a false choice between sound science and moral values," Obama declared as he signed documents changing U.S. science policy and removing what some researchers have said were shackles on their work.

"It is about ensuring that scientific data is never distorted or concealed to serve a political agenda — and that we make scientific decisions based on facts, not ideology," Obama said.

Researchers said the new president's message was clear: Science again matters in American life.

Opponents saw it differently: a defeat for morality in the most basic questions of life and death.

"The action by the president today will, in effect, allow scientists to create their own guidelines without proper moral restraints," Family Research Council President Tony Perkins said.

Scientists and patients crowded the East Room where the orders were signed.

The most immediate effect will allow federally funded researchers to use hundreds of new embryonic stem cell lines for promising, but still long-range research in hopes of creating better treatments, possibly even cures, for conditions ranging from diabetes to paralysis.

Until now, those researchers had to limit themselves to just 21 stem cell lines created before August 2001, when then-President Bush limited funding because of "fundamental questions about the beginnings of life and the ends of science."

Obama's actions yesterday align him with the scientists who had accused the Bush administration of placing political concerns over scientific data in its environmental and healthcare policy making. Many chafed at an administration they charged ignored important evidence about endangered species and scrubbed information from government reports of man-made global warming.

Yesterday, scientists focused on a new sense of freedom.

"I think patients everywhere will be cheering us on, imploring us to work faster, harder and with all of our ability to find new treatments," said Harvard Stem Cell Institute co-director Doug Melton.

In addition to the stem cell order, Obama issued a memo designed to ensure openness about scientific research and give whistleblower protection to scientists.

Promoting science "is about letting scientists like those here today do their jobs, free from manipulation or coercion, and listening to what they tell us, even when it's inconvenient — especially when it's inconvenient," Obama said.