The debate pits global opponents of abortion against many in the scientific community who see value in research involving cloning of stem cells taken from human embryos.
U.S. officials told reporters they would support a resolution on cloning put forward by Costa Rica and backed by about 40 other nations.
Other diplomats said the resolution would form a committee to negotiate a convention on cloning and instruct the panel to ensure the treaty forbids all forms of cloning.
"The draft resolution would try to predetermine the outcome of the negotiations," said one diplomat involved in the drafting negotiations, speaking on condition of anonymity.
While there are no competing resolutions at this time, this diplomat said, "Countries disagreeing with that outcome will be trying to press Costa Rica in coming weeks to open up the process so that a broader range of voices can be heard from."
