LONDON (AFP) - Britain has signed a legal treaty with Jordan giving guarantees that terror suspect Abu Qatada would face a fair trial if deported, Home Secretary Theresa May said on Wednesday.

She made the announcement in parliament a day after the Court of Appeal in London refused her permission to challenge its ruling that the radical preacher cannot be sent back due to rights concerns.

The minister also said the British government was "exploring all options" but refused to directly confirm reports that it was considering a temporary withdrawal from the European Convention on Human Rights.

"I can tell the house that I have signed a comprehensive mutual legal assistance agreement with Jordan," the minister said in a statement to the House of Commons.

"The agreement also includes a number of fair trial guarantees ... I believe these guarantees will provide the courts with the assurance that Qatada will not face evidence that might have been obtained by torture in a retrial in Jordan."

She said she believed the new treaty would give the British government "every chance of succeeding" in its years-long battle to deport Abu Qatada.

Both countries had yet to ratify the treaty and it was due to go before the Jordanian parliament shortly, Ms May said.

"I believe that the treaty we have agreed with Jordan, once ratified by both parliaments, will finally make possible the deportation of Abu Qatada," she said.

There was no immediate reaction from Amman.

The minister also reiterated that the British government would now apply directly to the Supreme Court to hear their appeal, despite the Court of Appeal's refusal to deal with the case.

A Spanish judge once branded Abu Qatada the right-hand man in Europe of Osama bin Laden, although Abu Qatada denies ever meeting the late Al-Qaeda leader.

The preacher was convicted in Jordan of terrorism charges in his absence, and is likely to face a retrial if he is returned.

But the European Court of Human Rights last year blocked his deportation over fears that evidence obtained through torture would be used against him in the new trial.

The government has repeatedly sought fresh assurances from Jordan about his treatment, but a Special Immigration Appeals Commission (SIAC) judge in November ruled again that he could not be sent back, a decision that was upheld by the Court of Appeal last month.