Kathleen Curry, 45, discovered her son lying on the floor of their room at the Sunset Beach Hotel in Patong Beach, Phuket, which was ravaged by the 2004 tsunami.

Connor Dean O’Keeffe was on holiday with his mother and her partner, David Skinner, 49, when the accident happened on Saturday.

Ms Curry denied suggestions from hotel staff that her son had been wet when he touched the game console’s electrical charger.

“He does it all the time at home,” she said. “There should be some kind of warning about the different electrical currents you get abroad because this wouldn’t have happened in England.

“I went into our apartment to look for him but he was lying dead on the floor. He was aware of the dangers of electricity and was not stupid. He would not mess around with plugs.”

His death led to warnings about electrical safety standards in Thailand, where most electrical plugs are two-prong, missing the third “earth” prong.

Ms Curry has returned home with his body to Southwark, South London. A British consular official said: “The paperwork was done quickly so they could take him home for a proper funeral.”

The Southwark Coroner has been informed and an inquest is expected to open soon.

Thai police have investigated Connor’s death and concluded that the hotel was not at fault. Police Lieutenant-Colonel Sopol Borirok said: “It was an accident.”

Wiraporn Ungathakorn, acting manager of the Sunset Beach Hotel, said: “The boy had been swimming and went back to his room. We believe he had plugged in his Gameboy or pulled at the charger while still wet. The water must have gone straight into the plug. The safety cut could not save him.

“He was found by his parents in the room and we sent him to hospital by ambulance. Doctors could not save him. The hotel has paid his medical fees. This was a tragic accident.”

Although the death has been logged as an accident, the electrical system in Thailand is regarded as dangerous by Western standards. Five years ago a young Danish boy was killed at a Thai hotel when he came into contact with an exposed wire by a lamp illuminating the swimming pool.

Even when there are three prongs, tourists are warned not to assume that the sockets are wired properly. In the past ten years, because of increased enforcement of safety standards, more three-pronged sockets have been fitted, but recent tests have shown that less than half are properly wired.

A spokesman for the Association of Electricity Producers said: “Safety standards are extremely high in Britain, with special agencies and regulators checking that standards are observed. You can assume that standards are not so high in the Far East.”

If the plug into which Connor plugged his Game- boy charger was not earthed it would not be considered a matter of negligence in Thailand.

The authorities in Phuket fear that such incidents could affect tourism. Two years after the tsunami, the island has only just recovered its previous visitor numbers. The Sunset Beach Hotel is on the beach road two miles north of Patong Beach near Kamala, a Muslim community that was devastated by the tsunami. In all, 262 people died in Patong and Kamala Bay.

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