Abu Hamza's extradition was approved by the home secretary
Jailed Muslim cleric Abu Hamza al-Masri has lost his High Court bid against extradition to the US where he faces terror-related charges.
The Egyptian-born preacher is currently serving a seven-year jail term in the UK for inciting murder and race hate.
Abu Hamza, 50, from west London, is wanted by US authorities on 11 charges, including sending cash to al-Qaeda.
He has 14 days to decide whether he will launch a final appeal in the House of Lords against the judges' decision.
The extradition order was first approved by City of Westminster Magistrates' Court and ratified by the Home Secretary, Jacqui Smith in February 2008.
Sir Igor Judge and Mr Justice Sullivan, sitting at the High Court, ruled the decision to extradite was "unassailable".
Lawyers for Abu Hamza had argued that there was evidence that torture had been used on some individuals in gathering the information which led to the US extradition request.
They said his US trial would be unlawful as he would be tried "on the basis of the fruits of torture".
They also contended that the decision to extradite would be incompatible with Hamza's human rights, and any further trial should take place in London.
Abu Hamza is already serving a seven-year sentence
The judges said the argument that the US evidence was "tainted by torture", and therefore inadmissible, was flawed.
They ruled that none of the material relied on by the US authorities "carries anything of the smell of the torture chamber sufficient to require its exclusion in a trial in this country".
The allegation of torture had also been made in the "most general terms, unsupported by evidence".
The charges against Abu Hamza include allegations that he attempted to set up an al-Qaeda training camp in Oregon between 1998 and 2000, and that he sent funds and recruits to the Taleban.
He also stands accused of involvement in a conspiracy to take 12 westerners hostage in Yemen in 1998.
It is alleged Abu Hamza - who is missing an eye and his hands - gave advice to the hostage-takers and provided them with a satellite phone.
Four of the captives - Britons Margaret Whitehouse, 52, a teacher from Hampshire; Ruth Williamson, 34, an NHS employee from Edinburgh; university lecturer Peter Rowe, 60, from Durham; and an Australian national, Andrew Thirsk - were killed after Yemeni authorities tried to rescue them.
The US charges against Abu Hamza carry a potential jail sentence of 100 years.
Abu Hamza was convicted in February 2006 of 11 of the 15 charges he faced in the UK.
In addition to being jailed for soliciting murder, he was also found guilty of inciting racial hatred, possessing "threatening, abusive or insulting recordings" and for having a document useful to terrorists.
He was arrested on an extradition warrant issued by the US government in May 2004 but the process was put on hold while he stood trial in Britain and attempted to appeal against his UK convictions.
Abu Hamza's lawyers now have 14 days to decide whether to appeal to the House of Lords. If they do not pursue this option - or an appeal is rejected - the extradition to the US would have to follow within 28 days.