Rumours that the terrorist suspect planned to pack an aircraft with explosives and launch it at the Ducal palace containing George Bush have been given weight by the president of Egypt, Hosni Mubarak.

He said Islamist suicide pilots were originally intended to launch an attack on the Italian riviera.

"On June 13 of this year, we learned of a communique from Bin Laden saying he wanted to assassinate Mr Bush and other G8 heads of state during their summit in Italy. It was a well-known piece of in formation," said President Mubarak.

On a state visit to Paris, the president told French media that Egypt's intelligence services had intercepted plans for "an aeroplane stuffed with explosives" to plunge into Genoa. A warning was passed to the US, he said.

When they installed a missile defence system at Genoa's airport in July and enforced a no-fly zone, the Italian authorities were derided, but now they feel vindicated.

After President Mubarak went public, Italy's deputy prime minister, Gianfranco Fini, confirmed that his own intelligence services had briefed him about the threat. They were expecting a small civilian aircraft with the range to fly from dozens of European airports, not a passenger jet.

"Many people joked about the Italian intelligence force. But actually, they had information that in Genoa there was the hypothesis of an attack on the American president with the use of an aeroplane. That is why we closed the airspace above Genoa and installed anti-aircraft missiles. Those who joked should now reflect," Mr Fini said.

In addition to President Bush and Vladimir Putin, the July 20-22 summit of the seven most industrialised countries plus Russia gathered the leaders of Britain, France, Germany, Italy, Canada and Japan.

Days before the summit the head of Mr Putin's personal protection force, General Yevgeni Murov, told the Russian news agency Itar-Tass that the US and Russian presidents were at risk. "Bin Laden utters threats to the US president," he was quoted as saying.

Italian media at the time also reported that Germany's intelligence service had relayed to Rome notice of a Bin Laden plot. That prompted the former CIA chief, Vincent Cannistrano, to hypothesise about an attack at the time deemed fanciful: "It would be simple to put explosives in a toy plane and fly it into a room full of dignitaries."

The Egyptian president told Le Figaro that his knowledge was based on a video made by Bin Laden on June 13. "It spoke of assassinating President Bush and other heads of state in Genoa. It was a question of an aeroplane stuffed with explosives. These precautions then had been taken."

However, in a twist which casts doubt on President Mubarak, the New York Times reported that people who have viewed the tape said there was no reference to stuffing an aircraft with explosives or killing Mr Bush.

The British government was unable to confirm that there had been a threat to attack the Genoa summit.