The radical Islamist cleric Abu Qatada has been released from Long Lartin high-security prison in Worcestershire after a British court ruled that he should not be sent back to Jordan to face trial on torture-based evidence.

The terror suspect is being driven back to his home in north-west London, where he faces a curfew from 4pm to 8am enforced by an electronic tag and strict restrictions on who he can meet. The details of his bail conditions were expected to be released later on Tuesday.

His release came as it emerged that the home secretary, Theresa May, faces a lengthy timetable in her attempt to persuade the court of appeal to overturn the ruling on Monday by the special immigrations appeal commission.

She is also making preparations to put fresh pressure on the Jordanian authorities to assure the British courts that the terror suspect will face a fair trial if he is sent back. The king of Jordan is due to visit London later this month.

The deputy prime minister, Nick Clegg, said the government remained "absolutely determined" to secure Abu Qatada's deportation.

Abu Qatada was first detained in Britain as a terror suspect in 2002 and has been fighting his deportation for seven years. Earlier this year, May travelled to Jordan and secured assurances that he would not face a trial for bomb plot offences dating back to 1998 on evidence obtained by torture. But Siac ruled on Monday that despite the assurances there remained a real risk that torture-based evidence would be used against him.

David Anderson, QC, the official reviewer of the terror laws, said it was a very frustrating episode for all involved but it was not the end of the road. He told the BBC that the key to the case really lay with the Jordanians.

"What the judge said, what the court said in terms, was that a simple amendment to the Jordanian criminal code so as to remove an ambiguity that is in it at the moment ought to suffice to make deportation possible, because it would then be possible to say without fear of contradiction that Abu Qatada, if placed on trial back in Jordan, would not be tried on the basis of evidence obtained by torture," he said.

Jordan's acting information minister, Nayef al-Fayez, said his government shared UK authorities' disappointment at the Siac ruling and said that the kingdom's constitution and constitutional court guaranteed a fair trial.

Abu Qatada's solicitor, Gareth Peirce, has welcomed the Siac ruling, saying: "It is important to reaffirm this country's position that we abhor the use of torture and a case that was predicated upon evidence from witnesses who have been tortured is rejected – rejected by the courts of this country as by the European court of human rights," she said.

"We clearly agree with the decision, but it is important to emphasise the fundamental rules of law that we subscribe to. To that extent, it is important for other cases, not just for this case."

May could face a lengthy legal process in her attempt to get the court of appeal to overturn the Siac ruling.

The Judicial Communications Office said the home secretary had 21 days from the date of the judgment to lodge an appeal on a point of law to the higher court.

An appeal court judge will then consider whether or not the home secretary has a case on the basis of her written submissions. If the judge rejects her appeal she can then request an oral hearing in front of three appeal court judges to review the decision. This process is likely to last until well into the new year.

If the court of appeal turns down the home secretary, Abu Qatada's lawyers are likely to apply for his stringent bail conditions to be lifted. The home secretary will then be faced with the option of whether or not to impose a terrorism prevention and investigation measures order (Tpim) – called a "control order lite" by some critics – on the basis that he is an international terror suspect. The Tpim can last a maximum of two years, which could mean that Abu Qatada could walk totally free on the streets of London just before the next general election.