Chicago ? The American Medical Assn. endorsed cloning for research purposes Tuesday, putting the nation’s largest organization of doctors officially at odds with the Bush administration.

The policy, adopted without debate at the AMA’s annual meeting, says cloning for research purposes is ethical. But the policy allows doctors who oppose the practice to refuse to perform it.

The measure does not support reproductive cloning and is strong in its call for proper oversight.

This is the first time the 260,000-member AMA has taken a position on what is known as therapeutic cloning.

The Bush administration opposes all cloning, research or reproductive, and the U.S. House earlier this year passed a White House-backed ban on any form of the practice.

“The AMA is not bucking the president,” said Dr. Michael Goldrich, incoming chairman of the committee that drafted the report. “The AMA is giving guidance to physicians.”

The proposal focused on a laboratory procedure designed to create human embryos for their stem cells, which are master cells that can potentially grow into any type of human tissue. Scientists believe such cells could someday be used to treat a wide range of human diseases.

Such embryos could theoretically develop into a human if implanted in a woman’s uterus. But the embryos are destroyed in the laboratory when the stem cells are taken.