A worldwide treaty to ban human reproductive cloning is a step closer after the United Nations General Assembly's legal committee set up a working party to draft an agreement. However the process is expected to take years, with all 190 member nations given the opportunity to have their say. Controversial scientist Dr Severino Antinori has already said that he is working to create the first human clone and although many experts say it could be some years before he succeeds, he says that technical advances mean that success could be swift. Any attempt to create a human clone would be fraught with dangers for mother and child. For example, Dolly the sheep, was the only success in 247 attempts at cloning sheep, and many cloned animal foetuses develop with severe abnormalities and spontaneously abort, often putting the mother's life at risk in the process. Dr Antonori says he has found a way of screening embryos to cut the number of failed pregnancies, but other doctors say there is no way to detect those which will not develop normally. There has been widespread condemnation of any attempt to create a baby through cloning, and countries are introducing their own legislation to outlaw human cloning. The US is heading for a ban on all human cloning, and it is already banned in the UK after a hastily drafted law passed through Parliament late last year. The creation in the US of 'the first human embryo clone' was widely reported last year, but there was no attempt to implant this in a woman. This prompted European Research Commissioner, Philippe Busquin to sum up European opposition: 'Not everything that is scientifically possible and technologically feasible is necessarily desirable or admissible,' he said. 'The developments in the USA demonstrate the urgency and importance of a European debate and position on research involving embryonic stem cells.' However, the use of cloning technology is highly controversial as other researchers are concerned that an outright ban on cloning human embryos could jeopardise future medical research. In particular, some see embryo clones as a source of stem cells, which may one day help provide treatments for many different diseases.