Our understanding of clone science is "too meagre" at present for human cloning to succeed, and many of the scientists involved are driven by money, according to a Nobel Prize-winning scientist who is attending a conference in Dublin.
"Inevitably the problems will be overcome, and it's then that the real ethical problems begin," said Prof Sir Joseph Rotblat, veteran atomic scientist turned peace campaigner.
His comments follow an announcement by Prof Severino Antoniori in the US last week that he intends to start cloning human embryos before the end of the year.
Prof Rotblat resigned, on ethical grounds, from the second World War project to develop the atom bomb and then went on to become a founder-member of the science ethics Pugwash Movement.
He was speaking yesterday to an international audience of young science researchers at the International Conference of Physics Students at Dublin City University. These conferences are aimed at building relationships between young scientists around the world.
"Ethics are not absolute, they change with environment and community," Prof Rotblat told The Irish Times after his address. "Look at in-vitro fertilisation. This was originally considered unethical but is now widely accepted."
On cloning he said: "I feel that this, too, will become acceptable."
The London-based professor earned a Nobel Peace Prize in 1995 for co-founding the Pugwash Movement, originally aimed at preventing the Cold War from heating up.
Recently he has encouraged all scientists to pledge themselves to a code of conduct resembling the medical profession's Hippocratic oath. The code reminds scientists that with knowledge comes responsibility.
"Scientists have to overcome the narrow interests of individual nations in their work. They are already an international fraternity and so are in a good position to do this," he said.
"It is important for scientists to debate with the public about what they do and show that they are not a secret society plotting against humanity."
Prof Rotblat (93) is the only surviving signatory of the Bertrand Russell-Albert Einstein Manifesto issued in London in 1955. The document urged governments to renounce war in an effort to avoid ending the human race in nuclear conflagration.
He urges all national academies of sciences to declare that ethical issues are an integral part of the work of scientists and to set up ethical committees.