The U.N. General Assembly's legal committee has begun debate on a measure to ban human cloning worldwide.
The 191 member nations are in almost unanimous agreement that cloning should be banned, but they differ on whether the ban should extend to embryonic stem cells now used in medical research.
One draft being discussed Thursday - written and sponsored by the United States, Costa Rica, and about 50 other nations - would include stem cells in the global ban. That version is supported by the Vatican and many predominantly Catholic countries.
But a second draft sponsored by Belgium and about 20 other countries would leave the decision on banning embryonic stem cell research to individual governments.
The cloning ban has been under consideration since 2001, but the legal committee in 2003 voted to delay acting on the global treaty for one year.