Radical cleric Abu Hamza has launched a last-minute British High Court bid to avoid extradition to the United States, it has been confirmed.
A second terror suspect, Khaled Al-Fawwaz, has also mounted a legal challenge.
It is expected that their applications will be heard as a matter of urgency, but no date has yet been set.
The move for injunctions was confirmed by a spokeswoman for the Judicial Office.
The latest legal action comes after Europe's human rights judges rejected a bid for an appeal by Hamza and four other terror suspects, paving the way for their extradition.
A panel of five judges threw out their request to the Grand Chamber of the European Court of Human Rights.
Hamza, who was jailed for seven years for soliciting to murder and inciting racial hatred, has been fighting extradition since 2004.
Computer expert Babar Ahmad, who was also subject to the ruling, has been held in a UK prison without trial for eight years after being accused of raising funds for terrorism.
After the ruling, the Home Office said Hamza and Ahmad, with Seyla Talha Ahsan, Adel Abdul Bary and Al-Fawwaz, would be "handed over to the US authorities as quickly as possible".
A Home Office spokeswoman said: "The European Court of Human Rights ruled there was no bar to the extradition of these men. We will continue working to ensure they are handed over to the US authorities as soon as possible."