It was routine - an ordinary gall bladder operation - except for a single, extraordinary detail. The patient was on an operating table in Strasbourg. The surgeons were in New York, nearly 4,000 miles away.

The announcement yesterday that surgeons had, for the first time, carried out a transatlantic operation, with a robot surgeon in one continent mimicking the real-time hand movements of a live doctor in another, ushers in a new era for medicine. The first transatlantic operation went well - but it is now also possible for a surgeon in one country to inadvertently cause the death of a patient in another. The revolutionary operation was carried out by Michel Gagner and Jacques Marescaux, from Mount Sinai Medical Centre in New York. Their patient, a 68-year-old volunteer, was in an operating the atre at the European Institute of Telesurgery in Strasbourg.

"It's a phenomenal step and we can't even begin to imagine the implications for medicine ... the barriers of space and distance have collapsed," said Professor Marescaux, of France's Research Institute Against Cancers of the Digestive Tract.

"I think it's a significant milestone in the 21st century. Four thousand miles - it's incredible," said Prof Gagner. "We were both nervous, but it all went so smoothly and beautifully, and by the end, we kind of knew something important had happened, and so it was an exhilarating moment."

Watching the operation on two screens, the surgeons in the US manipulated their instruments using tweezer-like controls attached to swivelling arms equipped with sensors to follow their tiniest movement.

The sensors translated the movements into digital signals, which were sent across the Atlantic to France along a high-speed optical fibre link. These signals were fed into the arms of a robot surgeon, which copied the surgeons' movements exactly. The cameras then relayed back to the surgeons what the robot - or they - had just done. Because the signals had to travel over 10,000 miles there was a delay of over one-tenth of a second after the surgeons made an incision before they saw the effects on the monitors.

"As a surgeon, it's only with this delay that I've realised how fast we operate," said Professor Gagner.

The data link, capable of carrying 10 megabytes of data a second, was the result of two and a half years' work by France Telecom. A surgical team was on standby in Strasbourg to intervene in case the transmission went down.

Telesurgery offers the opportunity for rare surgical expertise to be deployed almost instantaneously anywhere in the world, from one country to another.

"It may take 10 or 15 years before these systems become affordable, and every institution is connected," said Prof Gagner. "But I think it will happen.

"I think also that the next stage will be the addition of artificial intelligence to these robots. Right now the surgeons make the movements, but in the near future AI could be helping them make decisions."