A radical Muslim cleric -- once described as Osama bin Laden's right-hand man in Europe -- was on Tuesday ordered back behind bars in Britain after breaching his bail terms.

The Special Immigration Appeals Commission (Siac) was told that Abu Qatada, who was on a 22-hour curfew until being arrested last month, had plotted to leave Britain.

"For the reasons outlined in the judgment, the Commission revokes bail and directs that (Qatada) be detained under immigration powers," said judge John Mitting after a short hearing.

Home Secretary Jacqui Smith welcomed the decision, saying: "He poses a significant threat to our national security and I am pleased that he will be detained pending his deportation, which I'm working hard to secure."

The 47-year-old -- real name Omar Mahmoud Mohammed Othman -- has been convicted of terrorism charges in Jordan but Britain cannot deport him due to a court ruling in May which found that he could face mistreatment there.

Qatada -- who was labelled Bin Laden's "right-hand man" by a leading Spanish anti-terror judge -- gained refugee status in Britain in 1994 and has been in and out of prison since.

He was released most recently in June on a strict form of bail and re-arrested in November, although the exact circumstances around his detention remain secret.

Under his bail terms, Qatada was notably banned from attending any mosques, leading prayers, giving lectures, or "providing religious instruction" to anyone except his wife and children.

He was also banned from associating with a list of named people, including Bin Laden, as well as the Al-Qaeda leader's deputy Ayman al-Zawahiri.

The British government says burly firebrand Qatada had "long-established" links to extremists across the world, including Al-Qaeda and armed Islamist groups in Algeria, Tunisia and Egypt.

Others said to have sought his advice include "shoe bomber" Richard Reid and the "20th hijacker" Zacarias Moussaoui, the only man to have been convicted in connection with the September 11, 2001 attacks on the United States.

In its judgment Tuesday, the tribunal said the decision to revoke Qatada's bail was based on evidence not revealed openly to the tribunal for security reasons.

The tribunal "relies on information contained in the closed case to justify the revocation of bail," it said, although it did note that "the risk of Abu Qatada absconding has increased since his release in June 2008."

The judges also noted Qatada's desire to leave Britain and live in a country other than Jordan.

"We have accepted as true his declared wish to depart lawfully to a state or territory other than Jordan if the authorities of that state or territory can be persuaded to accept him," it says.

"We also accept as true... his declared interest in renouncing his Jordanian citizenship and seeking to live in the territory of his birth, Palestine.

"We do not, however, see any realistic prospect that either of these two possibilities will be open to him in the near or medium term," the judges said.