A controversial fertility doctor claimed yesterday to have cloned 14 human embryos and transferred 11 of them into the wombs of four women who had been prepared to give birth to cloned babies.

Watch the exclusive video of Panayiotis Zavos creating embryos before injecting them into wombs of women wanting cloned babies

The cloning was recorded by an independent documentary film-maker who has testified to The Independent that the cloning had taken place and that the women were genuinely hoping to become pregnant with the first cloned embryos specifically created for the purposes of human reproduction.

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Panayiotis Zavos has broken the ultimate taboo of transferring cloned embryos into the human womb, a procedure that is a criminal offence in Britain and illegal in many other countries. He carried out the work at a secret lab-oratory, probably located in the Middle East where there is no cloning ban. Dr Zavos, a naturalised American, also has fertility clinics in Kentucky and Cyprus, where he was born. His patients – three married couples and a single woman – came from Britain, the United States and an unspecified country in the Middle East.

None of the embryo transfers led to a viable pregnancy but Dr Zavos said yesterday that this was just the "first chapter" in his ongoing and serious attempts at producing a baby cloned from the skin cells of its "parent".

"There is absolutely no doubt about it, and I may not be the one that does it, but the cloned child is coming. There is absolutely no way that it will not happen," Dr Zavos said in an interview yesterday with The Independent.

"If we intensify our efforts we can have a cloned baby within a year or two, but I don't know whether we can intensify our efforts to that extent. We're not really under pressure to deliver a cloned baby to this world. What we are under pressure to do is to deliver a cloned baby that is a healthy one," he said.

His claims are certain to be denounced by mainstream fertility scientists who in 2004 tried to gag Dr Zavos by imploring the British media not to give him the oxygen of publicity without him providing evidence to back up his statements. Despite a lower profile over the past five years, scores of couples have now approached Dr Zavos hoping that he will help them to overcome their infertility by using the same cloning technique that was used to create Dolly the sheep in 1996.

"I get enquiries every day. To date we have had over 100 enquiries and every enquiry is serious. The criteria is that they have to consider human reproductive cloning as the only option available to them after they have exhausted everything else," Dr Zavos said.

"We are not interested in cloning the Michael Jordans and the Michael Jacksons of this world. The rich and the famous don't participate in this."

It took 277 attempts to create Dolly but since then the cloning procedure in animals has been refined and it has now become more efficient, although most experts in the field believe that it is still too dangerous to be allowed as a form of human fertility treatment. Dr Zavos dismissed these fears saying that many of the problems related to animal cloning – such as congenital defects and oversized offspring – have been minimised.



"In the future, when we get serious about executing things correctly, this thing will be very easy to do," he said. "If we find out that this technique does not work, I don't intend to step on dead bodies to achieve something because I don't have that kind of ambition. My ambition is to help people."



Dr Zavos also revealed that he has produced cloned embryos of three dead people, including a 10-year-old child called Cady, who died in a car crash. He did so after being asked by grieving relatives if he could create biological clones of their loved ones.



Dr Zavos fused cells taken from these corpses not with human eggs but with eggs taken from cows that had their own genetic material removed. He did this to create a human-animal hybrid "model" that would allow him to study the cloning procedure.



Dr Zavos emphasised that it was never his intention to transfer any of these hybrid embryos into the wombs of women, despite Cady's mother saying she would sanction this if there was any hope of her child's clone being born.



"I would not transfer those embryos. We never did this in order to transfer those embryos," Dr Zavos said. "The hybrid model is the thing that saved us. It's a model for us to learn. First you develop a model and then you go on to the target. We did not want to experiment on human embryos, which is why we developed the hybrid model."



Dr Zavos is collaborating with Karl Illmensee, who has a long track record in cloning experiments dating back to pioneering studies in the early 1980s. They are about to recruit 10 younger couples in need of fertility treatment for the next chapter in his attempts at producing cloned babies.



"I think we know why we did not have a pregnancy," said Dr Zavos. "I think that the circumstances were not as ideal as we'd like them to be. We've done the four couples so far under the kind of limitations that we were working under.



"We think we know why those four transfers didn't take. I think with better subjects – and there are hundreds of people out there who want to do this – if we choose 10 couples, I think we will get some to carry a pregnancy."



All the cloning attempts, which date back to 2003, were filmed by Peter Williams, a distinguished documentary maker, for the Discovery Channel, which will show the programme tonight at 9pm.



Williams said that he was present at the secret laboratory when the cloning was carried out by Dr Illmensee. "There's never been any question of concealment, because we'd have known about it," Williams said.



The little girl who could 'live' again

Little Cady died aged 10 in a car crash in the US. Her blood cells were frozen and sent to Dr Zavos, who fused them with cow eggs to create cloned human-animal hybrid embryos.



These hybrid embryos were developed in the test tube and used to study the cloning process, but were not transferred into a human womb, despite Cady's mother saying she would sanction this if there was a chance the clone of her little girl could be born. Dr Zavos said he would never transfer hybrid animal clones into the human womb.



However, cells from Cady's "embryo" could in the future be extracted from the frozen hybrid embryo and fused with an empty human egg with its nucleus removed. This double cloning process could produce a human embryo that Dr Zavos said could be transferred into the womb to produce Cady's clone.



Frontiers of fertility: The key questions



Q. What does he claim to have done?



A. Panayiotis Zavos says he has created 14 human embryos and transferred 11 of them into the wombs of four women. Some of these embryos only developed to the four-cell stage before being transferred, but some developed to the 32-cell stage, called a morula. He also claims to have created human-bovine hybrid clones by transferring the cells of dead people into the empty eggs of cows. However, these hybrid embryos were used for research purposes and were not transferred to the womb.



Q. How does this compare to scientists' previous achievements?



A. Other scientists have created human-cloned embryos but not for the purposes of transferring them to wombs in order for women to give birth to babies. Those researchers created cloned human embryos in the test tube to extract stem cells for research. Dr Zavos has gone further (and broken a taboo) by creating embryos specifically for human reproduction, and he has attempted to create a viable pregnancy by transferring the cloned embryos into women.



Q. Hasn't he made similar claims before?



A. In 2004, Dr Zavos claimed to have transferred a cloned human embryo into a woman's womb but did not produce hard evidence. He has now produced more cloned human embryos, some at an advanced stage, and transferred them into the wombs of three more women. An independent documentary maker vouches for him.



Q. Why is this such a controversial thing to do?



A. Studies on animal cloning have shown time and time again that it is unsafe. The cloned animals suffer a higher-than-normal risk of severe developmental problems and the pregnancies often end in miscarriage. Mainstream scientists believe cloning is too dangerous to be used on humans.



Q. How likely is it that he will succeed?



A. He is determined to succeed and has a long line of people eager to sign up to his cloning programme, at a cost of between $45,000 and $75,000. Cloning attempts in other species, including primates, suggest there is no insuperable barrier to cloning humans.

Watch the exclusive video of Panayiotis Zavos performing the cloning procedure