Britain's High Court is set to rule on whether Abu Hamza al-Masri, who is accused of helping set up a "terrorist" training camp in the US state of Oregon, can be extradited to the United States where he is wanted to face charges.
UK judges Duncan Ouseley and John Thomas are handing down the judgment on Friday in the case of al-Masri, who allegedly also turned London's Finsbury Park Mosque into a training ground for fighters.
Al Masri, who has been in jail in Britain since 2004, and four other men also suspected of terrorism have been fighting extradition for years. Both British and European courts have ruled that they can be sent to the US to face charges.
The suspects applied to the High Court for a last-minute halt, with al-Masri's lawyers saying his deteriorating health means it would be "oppressive" to send him to a US prison.
Lawyers for al-Masri, who has one eye and hooks in place of hands he claims to have lost fighting the Soviets in Afghanistan, said he suffered from depression, chronic sleep deprivation, diabetes and other ailments and was in need of medical tests.
Also learning whether they can be extradited are Babar Ahmad, Khaled al-Fawwaz, Adel Abdul Bary and Syed Ahsan.
Ahmad, a computer expert from South London, has been held in a UK prison without trial for eight years after being accused of raising funds for terrorism with his co-accused, Ahsan, through a website.
Bary and al-Fawwaz were indicted with others, including Osama bin Laden, for their alleged roles in the bombings of two US embassies in east Africa in 1998. Al-Fawwaz faces more than 269 counts of murder.
The various extradition bids have dragged on for as long as 14 years amid wrangles over whether the defendants' human rights would be respected by US authorities.
Government lawyer James Eadie said this week that no further appeals would be possible if the High Court judges ruled against the suspects.
He said in that case the government would be entitled to "move instantly" to deport the men.