Milk from the offspring of cloned cows is secretly - and illegally - going into high street shops.
Despite deep unease among consumers, the milk is not being labelled or identified in any way, leaving shoppers in the dark about what they are drinking.
The dairy farmer involved said he wanted to remain anonymous because the British public regards cloning as so distasteful that buyers would stop taking his milk.
Last night the Food Standards Agency said it would investigate. It told the Mail that it believes the sale of milk from such cows is illegal under food regulations.
Research has identified serious concerns for the health and well-being of animals produced as a result of cloning. There is evidence of premature births, deformities and early death.
The cows being used to produce the controversial milk start life in the U.S. as embryos created from the eggs of cloned prize-winning Holstein cows and the sperm of normal bulls.
The embryos are frozen and flown to the UK, where they are implanted into host cows.
The resulting supersize animals can be used to produce massive quantities of milk and for breeding purposes.
The Mail blew the whistle on this trade in 'clone farm' cows more than three years ago following the birth of Dundee Paradise on a farm in Shropshire.
Subsequently, we revealed that a total of eight such calves were born on British farms.
It now appears that milk from at least one of these animals, and possibly many more, is being sold for human consumption.
The Mail revelations in 2007 were a complete surprise to the Government's food and farming department, Defra, and the FSA, which had no knowledge of the births.
Subsequently, the EU and the European Food Safety Authority (EFSA) launched a major investigation in order to decide on how to handle the controversial technology.
As a result, earlier this month, Euro MPs voted in favour of a ban on meat and milk from clones and their offspring going into human food without approval. However, the regime has not yet been passed into law.
Details of the claims that clone farm milk is reaching the public appeared in the respected International Herald Tribune.
It said a British dairy farmer had admitted using milk from a cow bred from a clone as part of his daily production.
The man said he was also selling embryos from the same cow to breeders in Canada.
He said part of the reason he was staying anonymous was that he did not want to be required to get rid of a valuable cow.
An FSA spokesman said: 'Since 2007 the FSA interpretation of the law has been that meat and products from clones and their offspring are considered novel foods and would therefore need to be authorised before being placed on the market.
'As the UK authority responsible for accepting novel food applications, the agency has not received any applications relating to cloning and no authorisations have been made.
'The agency will, of course, investigate any reports of unauthorised novel foods entering the food chain.' European experts have not identified a food safety risk associated with cloning.
But some campaigners claim it could allow new diseases to pass from farm animals to humans.
The RSPCA and Compassion in World Farming (CiWF) are among a number of groups opposed to farm animal cloning for food. The chief policy adviser to CiWF, Peter Stevenson, said: ' I would be appalled if milk from a clone offspring cow is coming into the food chain in the UK.
'As the farmer has acknowledged, the public is deeply concerned about this and does not want it.
'If this is happening, it demonstrates that there are very serious loopholes in the way food production is policed in this country.
'The Government has known these animals were in the country for at least three years, but it appears to have done nothing to ensure any milk or meat is not reaching the public.'
A study conducted by the FSA found widespread opposition to clone farming and food. Dr Steve Griggs, who led the research, said: 'The majority of people came to the conclusion that they would not want to eat such food. The overwhelming majority either did not want it or were unsure.
'They struggled to identify any convincing benefits for them as consumers.
'There were concerns about the ethical side of animal cloning, indeed whether we have the moral right to go down this road.'