U.S. President Barack Obama signs an executive order on Monday that reverses restrictions on federal funding of embryonic stem cell research. (Gerald Herbert/Associated Press)

U.S. President Barack Obama has signed an executive order lifting funding limits on research with embryonic stem cells imposed by his predecessor, George W. Bush.

"Today, with the executive order I am about to sign, we will bring the change that so many scientists and researchers, doctors, and innovators, patients and loved ones have hoped for, fought for these past eight years," Obama told reporters at a news conference at the White House on Monday.

"We will lift the ban on federal funding for ... embryonic stem cell research."

The long-promised move will allow a rush of research aimed at one day better treating, if not curing, ailments from diabetes to paralysis — research that has drawn broad support, including from notables like Nancy Reagan, widow of the late Republican president Ronald Reagan.

Under Bush, taxpayer money for that research was limited to the 21 stem cell lines that were created before Aug. 9, 2001. But researchers have said that these lines have, in many cases, had some drawbacks that limited their potential usability.

The research is controversial because days-old embryos must be destroyed to obtain the cells. They typically are culled from fertility-clinic leftovers otherwise destined to be thrown away.

"In recent years when it comes to stem cell research, rather than furthering discovery, our government has forced what I believe is a false choice between sound science and moral values," Obama said.

"In this case the two are not inconsistent. As a person of faith I believe we are called to care for each other and work to ease human suffering."

Obama qualified his support for stem cell research by saying that his administration "will never undertake this research lightly."

"We will support it only when it is both scientifically worthy and responsibly conducted. We will develop strict guidelines which we will rigorously enforce, because we cannot ever tolerate misuse or abuse."

Obama also said his administration will never open the door to human cloning, which he called "dangerous." Embryonic stem cells are master cells that can morph into any cell of the body. Scientists hope to harness them so they can create replacement tissues to treat a variety of diseases — such as new insulin-producing cells for diabetics, cells that could help those with Parkinson's disease or maybe even Alzheimer's, or new nerve connections to restore movement after spinal injury.

Change gives greater flexibility for research

Since Bush's decree, hundreds of new stem cell lines have been created. Researchers say these new lines, funded by private dollars, are healthier and better suited to creating treatments for people rather than doing basic laboratory science.

Obama's change does not fund creation of new lines. But it means that U.S. scientists who until now have had to rely on private donations to work with these newer stem cell lines can apply for government money for the research, just like they do for studies of gene therapy or other treatment approaches.

The reversal of the Bush ban on funding for new lines fulfills a promise made repeatedly by Obama during his presidential campaign. Obama called on Congress to "act on a bipartisan basis" to provide further support to stem cell research.

But critics have questioned Obama's eagerness in implementing the change at a time when the United States is struggling through a severe economic tailspin.

Eric Cantor, the No. 2 Republican in the House, said in a Sunday interview with CNN that the White House should focus on the economy instead.

"[Obama's] response to that is that the economy's a big problem, it's going to take a long time to turn around so we can do other things at the same time," said the CBC's Paul Hunter from Washington, D.C.

"Nonetheless, he's doing it very quickly and ... sending that strong signal in his remarks there that his administration wants to put science ahead of ideology."

Obama also announced Monday that his administration would draw up "a strategy for restoring scientific integrity to government decision-making."

The strategy would "ensure that in this new administration we base our public policies on the soundest science, that we appoint scientific advisers based on their credentials and experience, not their politics or ideology."

He did not offer further details.

With files from the Associated Press