LONDON — The international community faces a stark choice: outlaw human cloning or prepare for the creation of cloned humans, U.N. researchers said Saturday.

Previous attempts to reach a binding worldwide treaty foundered over divisions on whether to outlaw all cloning or permit cloning of cells for research.

The best solution may be to ban human cloning, but to allow countries to conduct strictly controlled therapeutic research, including stem cell research, according to the report from the Japan-based United Nations University Institute for Advanced Studies.

Almost all countries oppose human cloning and more than 50 nations have introduced laws banning it. But lack of binding global legislation gives scientists an opening to create human clones in countries where bans do not exist.

“Failure to outlaw reproductive cloning means it is just a matter of time until cloned individuals share the planet,” said Brendan Tobin, a human rights lawyer who co-authored the report.

“If failure to compromise continues, the world community must accept responsibility and ensure that any cloned individual receives full human rights protection,” he said.

Cloning research proponents argue it offers great hope for producing replacement tissue and the potential for a cure for diseases such as cancer, Alzheimer’s, Parkinson’s and diabetes.

The report recommends permitting cloning cells for research — but not cloning aimed at duplicating a person or animal. It also calls for strict controls to prevent the uncontrolled production and destruction of embryos.