Europe's human rights judges will meet today to consider whether Jordanian terror suspect Abu Qatada's appeal over deportation should be allowed to go ahead.
A panel of five judges will hold talks on whether the case should be heard by the Grand Chamber of the European Court of Human Rights (ECHR) in Strasbourg.
But they may not reach their final decision today and, even if they do, they may not announce it until later, a spokesman for the court said.
They are also unlikely ever to reveal any reasons for their decision.
Qatada's appeal, lodged on April 17, prompted a row with Home Secretary Theresa May over whether the three-month appeal deadline from the court's original decision on January 17 expired on the night of April 16 or 17.
But it will remain unclear whether Mrs May was right to say that Qatada's appeal was made too late as the judges are likely to simply say whether or not the appeal against deportation can go ahead.
Very few Grand Chamber appeals are successful, but if the appeal is granted, Qatada, 51, is likely to apply to a senior immigration judge for bail and could be freed from Belmarsh high-security jail within weeks.
Qatada's legal team are challenging the court's decision that he could be sent back to Jordan with diplomatic assurances that he would not be tortured.
It is separate from the court's initial bar on deportation which required the Government to first get assurances from Jordan that evidence gained through torture would not be used against Qatada if he is sent back.
Repeated failed attempts by UK governments over the last 10 years to deport the radical cleric have cost nearly £1 million in legal fees, Government figures show.
Immigration Minister Damian Green said the bill since 2002 has reached £825,000 and is still growing.
No figures were given for how much Qatada, described by a judge as Osama bin Laden's right-hand man in Europe, has received in legal aid over that period.
Some estimates put the total cost of keeping Qatada in the UK, either in a high-security jail or closely monitored under strict conditions in the community, along with the legal costs of the fight to deport him, at more than £3 million.
Qatada, who is said to have wide and high-level support among extremists, was convicted in his absence in Jordan of involvement with terror attacks in 1998 and faces a retrial in his home country.
He also featured in hate sermons found on videos in the flat of one of the September 11 bombers.
Since 2001, when fears of the domestic terror threat rose in the aftermath of the attacks, he has challenged, and ultimately thwarted, every attempt by the Government to detain and deport him.
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