The President's Council on Bioethics was itself divided on what course Congress should take, but neither of two recommendations put forward supports the permanent ban favored by Mr. Bush and approved by the House last year.
A slim majority — 10 of 18 members — favored a four-year moratorium to allow for further public debate. Seven members argue that scientists should be allowed to move ahead under strict government regulations. One member failed to attend most meetings and took no position.
"The council, reflecting the differences of opinion in American society, is divided regarding the ethics of research involving cloned embryos," the report said. "Yet we agree that all parties to the debate have concerns vital to defend."
The report said members agreed it was better to air their differences than try to paper over them "in search of a spurious consensus."
The divided report was expected. In February, the council's chairman, Leon Kass, said opinions were so wide-ranging that he was abandoning hope of finding consensus. He said the council would instead produce two reports, outlining the pros and cons of each position.
Members agreed that cloning for reproductive purposes should be banned outright, for both practical and ethical reasons. In this procedure, a cell from one person would be used to create a second person with the same genetic code — like an identical twin born much later.
Scientists say the procedure would be extraordinarily dangerous because any baby produced would likely have severe deformities. Nonetheless, at least two scientists, including one in Kentucky, say they are trying to produce a cloned baby.
It was unclear what influence the report might have in the Senate, where members are also split over whether to allow cloning for research.
"It is my sincere hope that what we've done here will be of some help" in thinking through the issues, said Kass, a bioethicist at the University of Chicago.
Like senators, council members are divided on the central issue: the moral value of a human embryo compared with the promise of science to develop treatments for disease.
The idea, researchers say, is to create embryonic stem cells that could develop into compatible organs and replace a patient's ailing heart, liver or kidney.
Seven of the 18 members favored a total ban that Mr. Bush supports: "We believe it is morally wrong to exploit and destroy developing human life, even for good reasons."
They joined with three others who wanted a moratorium, which would give time to develop a system of regulation, to form the majority position.
The seven members in the minority argued that a days-old human embryo does not deserve the same protections afforded a human being and the moral objections to the research are outweighed by the good that could come from it.
"This research could provide relief to millions of Americans," they wrote.
Stacked with academics, the council's meetings have sounded more like graduate seminars than government deliberations. Members parried over the inherent dignity of human beings and debated, at length, the proper terminology to use in the discussion, with each phrase loaded in one direction or another.
While Kass repeatedly said the council's deliberations had little to do with the issue of abortion, the question of when life begins underscored the entire ethical debate.
Over several meetings, the council considered whether a human embryo deserves the same rights and protections that society affords people; whether it is a collection of cells with no rights at all; or whether it is something in between.
The House passed a total cloning ban last year, including reproduction and research. But the Senate has yet to act. Last month, a leading proponent of a total ban, Sen. Sam Brownback, R-Kan., said he would support a two-year moratorium on cloning for research, conceding he didn't have the votes for a permanent ban.