An Italian fertility expert will attempt to clone a human being within the next year.
Dr Severino Antinori says he has about 10 couples who are potential candidates for the procedure.
Speaking in Kentucky, USA, Dr Antinori said he is forming an "international coalition" of scientific experts to work on the project.
But David Magnus, an ethicist at the University of Pennsylvania, argued that scientists don't yet have enough knowledge to safely attempt human cloning.
"It's very risky and dangerous to be trying this long before we've worked out safe procedures and children can't consent to be born," Dr Magnus said.
Dr Antinori argued that his system is safe and that the chance to help infertile couples who otherwise could not have children outweighs objections. He is a pioneer in assisted reproduction techniques for patients with problems conceiving and developed methods that have allowed women in their late 50s and early 60s to become pregnant.
Human cloning loomed as a possibility after British scientists in 1997 announced the successful cloning of a sheep they named Dolly. Pigs and other animals have been cloned since then.
In 1998, Chicago physicist Richard Seed announced his intention to clone a human but never carried it out. The same year, South Korean scientists claimed to have cloned a human embryo, but they made no attempt to implant it into a woman's body to grow into an infant.
Dr Antinori would say only that the cloning project would be attempted in some country in the Mediterranean area.
The process would first require the removal of a few cells from somewhere on a male patient's body, perhaps the skin. Genetic material from the cells would be united with a normal human egg. The combined material then would be artificially "stimulated" to start cell division. After a few days, if all went well, the resulting embryo would be placed in a mother's womb to grow and develop into a baby.