HUMAN clones could in theory be born in less than two years, according to the scientist who led the work to produce Dolly the cloned sheep.
But Dr Ian Wilmut told MPs that he found the concept "distressing and offensive". His team had used more than 1,000 unfertilised eggs to make Dolly and this was a measure of the difficulties to be faced in cloning a human, he said.
In Britain, the Human Fertilisation and Embryology Authority records about 1,000 treatments each year with human eggs and has about 2,000 registered egg donors.
A project to clone humans would require a level of demand that would place a considerable burden on a system where eggs were already in short supply, said an authority spokesman.
Dr Wilmut, of the Roslin Institute near Edinburgh, was appearing before the Science and Technology Select Committee at the House of Commons and was asked how easy it would be to clone a person.
"I have hesitated to make predictions, but I am sure if you really wanted to do it you could do it," he said. "If you were prepared to make that sort of effort then you would expect to make significant progress in one or two years."
Dr Wilmut said that some widely publicised applications for human cloning were absurd. "It seems to me that most of the suggested applications for cloning of humans are nonsensical.
"The idea that you can bring back a child, that you can bring back your father, it is simply nonsensical. You can make a genetically identical copy, but you cannot get back the person you have lost."
He said it was the view of everyone at the institute and PPL Therapeutics, the company collaborating with the cloning research team, "that we would find this kind of work with human embryos offensive.
"We would support wholeheartedly the idea of prohibition in the most effective way possible".
Prof Grahame Bulfield, director of the institute, admitted he could see in extremis circumstances in which someone somewhere in the world might attempt human cloning.
Cloning work on farm animals would continue and PPL expected the first cloned cows to be born this year, he said. It was hoped that the technique would be perfected and extended to cattle and pigs within five to 10 years.
In time, 85 per cent of British cattle could be clones bred to match the qualities of the top 10 to 15 per cent of livestock. However, the scientists said it might take 20 years to achieve. Prof Bulfield said cloning cattle could be used to protect biodiversity, with clone cells frozen and stored to ensure breeds did not die out.
For British farmers to compete with foreign rivals it was necessary to improve the quality of livestock even if this led to over-production, he said.
Other uses of cloned animals in America were described yesterday to a Commons committee hearing. D Caird Rexroad Jr, of the US Agriculture Department, said his agency's scientists had been cloning farm animals using genes from embryos since 1986. It was also developing gene transfer techniques that would produce animals low in fat and resistant to disease.
James Geraghty, president of Genzyme Transgenics Corp, said his company was using cloning techniques to make animals whose organs could be used for human transplantation. Genetically-altered cows or goats, he said, could produce milk that contained drugs for the treatment of human disease.
Dr Susan Smith, director of the Oregon Primate Research Centre, said her researchers hoped to use cloning techniques to produce identical monkeys which could be used to test drugs. "Genetically-identical monkeys would revolutionise the use of non-human primates in biomedical research," she said.
