Manfo Asiedu, 34, was tasked with exploding his rucksack device on the tube at White City station but "lost his nerve at the last moment" and dumped it in woodland.

Ghanian-born Asiedu, of no fixed address, had pleaded guilty to conspiracy to cause explosions of a nature likely to endanger life between March and July 2005 at a previous hearing.

He sat smartly dressed in a suit in the dock at Kingston Crown Court, south-west London and stared straight ahead as he learned his fate.

Judge Mr Justice Calvert-Smith told him he would serve at least half of his sentence and recommended his deportation on his release.

He said he had lied on an "epic scale" about his involvement in the planning of the attacks in which four bombs were detonated on three tube trains and a bus, but the main charge failed to ignite.

He told Asiedu that he had done nothing to try and stop the "attempted mass murder" of innocent citizens and had denied the public an explanation for the motivation behind this "dreadful crime".

The court had heard that Asiedu had played a key role in buying ingredients for the devices and helped make up the home-made bombs on the eve of the attacks.

He lived in a one-bedroom flat, turned into a bomb-making factory in New Southgate, north London, with some of the men now convicted in connection with the attack. Following the failed suicide attacks he returned to the flat and tried to dispose of incriminating evidence by dumping it in the communal bins.

Asiedu was charged under the names of Sumaila Abubakhari, also known as Manfo Kwaku Asiedu, as he used fake identities since coming to the UK in December 2003. He changed his plea to guilty earlier this month at the last minute ahead of a retrial.