Repeated failed attempts to deport radical cleric Abu Qatada have cost nearly £1m in legal fees, the government confirmed.
Immigration Minister Damian Green admitted the bill since 2002 has reached £825,000 and is set to continue to grow.
Home Secretary Theresa May has come in for intense criticism over her handling of the case after confusion over an appeal deadline means Qatada could be released on bail within weeks.
Green said the tally related to legal fees incurred by the government in trying to return the cleric to Jordan.
No figures were given for how much Qatada, described by a judge as Osama bin Laden's right-hand man, has received in legal aid over that period.
The Legal Services Commission (LSC), which runs the legal aid scheme in England and Wales, confirmed last week the 51-year-old has been receiving public money to fund his appeals.
Qatada was arrested by officers from the UK Border Agency (UKBA) on the morning of Tuesday April 17, just hours after the Home Office said the time for any appeal was up.
But Qatada's lawyers claim their appeal to the Strasbourg-based court, made at 11pm local time (10pm BST) on April 17, was just before the midnight deadline.
A panel of judges at the human rights court will now decide whether the appeal was in time or not. If the deadline had expired, the judges have no discretion to allow the appeal to be considered by the court's Grand Chamber.
Green said: "Since 2002 the legal fees incurred by the government to deport Abu Qatada are around £825,000. The case is ongoing and so further costs are likely to be incurred."
Home Secretary Theresa May is trying to deport Qatada, who is currently in the high-security Belmarsh prison in south east London, to Jordan, where he faces a retrial on terror charges.
But she has warned it may be months before the 51-year-old is put on a plane.