Abu Qatada, a Muslim preacher once described as Osama bin Laden's right-hand man in Europe, has been released from a British prison on bail.
Qatada, who is fighting extradition to Jordan, was released from Long Lartin high-security prison in Worcestershire, central England on Monday, and will have to obey a 22-hour-a-day curfew at his home in London.
Ahead of his release, the Home Office, or interior ministry, said it would "exhaust all avenues" to ensure his extradition to Jordan, where he was convicted in his absence of involvement in terror attacks in 1998.
Britain says videotapes of his sermons were found in a German apartment used by three of the people who carried out al-Qaeda's September 11, 2001, attacks on the United States.
But the European Court of Human Rights has ruled that Britain cannot deport the Jordanian to his homeland because evidence used against him in any trial there may have been obtained through torture.
A spokeswoman for the Home Office told the AFP news agency: "Everyone is united in wanting this man deported.
"This government will exhaust all avenues open to get Qatada on a plane. If we do so, we will continue to negotiate with the Jordanians to see what assurances we can be given about the evidence used against Qatada in their court."
A junior Home Office minister, James Brokenshire, is travelling to Jordan this week after David Cameron, the British prime minister, spoke last week with King Abdullah II about finding an "effective solution" to the case.
Qatada's release nothwithstanding, it still means he will be under house arrest for 22 hours a day, will not be able to visit a mosque, and is banned from using the telephone and the internet.
He must also wear an electronic tag and non-family visitors to his home must be vetted beforehand by the security services.
The preacher, also known as Omar Othman, arrived in Britain in 1993 claiming asylum and has been fighting attempts to extradite him for more than six years, most of which he has spent in jail.
He has never been charged with a criminal offence in Britain. Qatada, a Jordanian of Palestinian origin, was labelled a key bin Laden aide in Europe by a Spanish judge.