Abu Qatada's appeal to European human rights judges against deportation to Jordan may have been lodged “just in time”, according to advice from the Council of Europe.
Home Secretary Theresa May told MPs that the application by Qatada's lawyers should be thrown out by the European Court of Human Rights (ECHR) as the three-month deadline had passed when it was submitted on Tuesday night.
However, Labour released advice from the research department of the Council of Europe - which is responsible for the court - suggesting it may have just beaten the deadline.
The note, sent to the House of Commons Library, stresses that the final decision on whether the appeal is admissible now rests with a panel of five judges from the court's Grand Chamber.
"The Othman (Qatada) case was supposed to become final on 17/04/2012 and, according to the information provided by the European Court, the applicant requested a referral to the Grand Chamber on the 17/04," the note said.
"So I would say that it just in time but of course the Court (panel) may decide otherwise."
The note was signed by Nathalie Chene of Secretariat of the Committee of Ministers Council of Europe.
Earlier, in the Commons, Mrs May was adamant that the appeal deadline had passed 24 hours earlier at midnight on Monday - April 16.
"The Government is clear that Abu Qatada has no right to refer the case to the Grand Chamber of the European Court of Human Rights, since the three-month deadline to do so lapsed at midnight on Monday," she said.
"The Government has written to the European Court to make clear our case that the application should be rejected because it is out of time."
On Tuesday, Mrs May announced Qatada had been rearrested and deportation proceedings resumed in the absence of any appeal against the court's ruling - issued on January 17 - that he would not face torture if he was deported to stand trial on terrorism charges in his native Jordan.
However that night at 11pm local time Qatada's lawyers lodged their appeal with the ECHR.
Today, amid noisy scenes in the Commons chamber, Mrs May accused the lawyers of using "delaying tactics" to hold up the deportation process.
She acknowledged, however, that proceedings would have to be put on hold while the Grand Chamber panel came to a decision on the admissibility of the appeal.
"They are the only final arbiters of what the deadline was," she said.
Pressed by Labour former home secretary Alan Johnson, she said that she took full responsibility for any error by the Government.
"I, of course, take responsibility for decisions that I have taken. This is not a question of what officials have done. I take full responsibility," she said.
Shadow home secretary Yvette Cooper said the "confusion" in the Home Office over the deadline date had played into the hand's of Qatada's lawyers, increasing the potential for delays and for Qatada to obtain bail.
She said that officials should have realised there could be a problem when journalists began querying the deadline date with them on Monday.
"When the Home Secretary is accused of not knowing what day of the week it is, chaos and confusion have turned into farce. But this farce has serious consequences," she said.
Among Tory MPs there was broad support for Mrs May coupled with frustration and anger at the prospect of further hold-ups at the hands of the ECHR.
Backbencher Charles Walker urged her to put the "scumbag and his murderous mates" on a plane out of the country and send "a metaphorical two fingers to the ECHR".
Outside the chamber, however, another Tory MP, Douglas Carswell, was scathing about the Government's handling of the case, saying it was "Carry on Sir Humphrey in the Home Office".
Campaigning in Scotland, David Cameron could not hide his exasperation at the latest setback.
"I sometimes wish I could put him plane and take him to Jordan myself. But Government has to act within the law. That is what we'll do. We will get this done," he said.