By David Morgan

GUANTANAMO BAY US NAVAL BASE, Cuba, Apr 26 (Reuters) An al Qaeda suspect who earned top privileges for good behavior in the U S prison camp at Guantanamo Bay, Cuba, asked a military judge today to overturn a camp rule that detainees who face trial be held in maximum security.

Sufyian Barhoumi, a 32-year-old Algerian charged with training two other al Qaeda militants to build remote detonators for car bombs, had been granted communal living, up to 14 hours a day outside his cell and family-style meals in an area reserved for detainees considered ''highly compliant.'' But weeks before his pretrial military tribunal hearing yesterday Barhoumi was suddenly transferred without explanation to a maximum-security facility where prisoners spend 22 hours a day locked inside cement cells and have little contact with fellow detainees.

Court documents say he now seldom sees the sun and is allowed out of his cell only for two hours of exercise in a 5-yard-by-10-yard (metres) recreation pen, often before sunrise.

Barhoumi's military lawyer, Army Captain Wade Faulkner, asked the tribunal's presiding officer, Navy Captain Daniel O'Toole, to reverse the transfer, saying the treatment threatened to undermine the defense case.

''Don't you see why he might be upset and perceive it as punishment?'' Faulkner asked as Barhoumi, a stocky bearded man who lost part of his left hand to a land mine in Afghanistan, looked on silently from the defense table.

A top prison official, identified as ''Col. B,'' testified that Barhoumi's transfer was under a policy meant to protect detainees charged with war crimes from threats by other prisoners. The transfer would also reduce chances that Barhoumi and other detainees heading for trial would try to escape or commit suicide.

''The real baseline for my whole motivation in everything is running a peaceful, safe and secure camp,'' said Col. B, who originated the policy.

He acknowledged that Barhoumi, whose record shows more than 18 months of good behavior, had not been subjected to threats and had never tried to escape or harm himself. Nor have there been threats against others facing trial, he said.

Nine of the 10 Guantanamo detainees charged so far are being held in a cement building known as Camp Delta 5, which was modeled after a maximum-security federal penitentiary in Indiana. The 10th detainee remains in a separate high-security area.

The 10, out of a prison population of 490, could receive maximum sentences of life in prison if convicted of war crimes.

The tribunals were established by US President George W Bush after the September 11 attacks. Their legality has been challenged before the Supreme Court, which is expected to rule in June.

Barhoumi and two alleged co-conspirators - Saudis Jabran Said bin al Qahtani and Ghassan Abdullah al Sharbi - have all had pretrial hearings scheduled for this week.

Qahtani boycotted his hearing yesterday and condemned the United States as an enemy of God. He said he would rather be killed than go to trial and warned court officials that they would ''regret everything'' if he escaped.

All three men were captured in March 2002 by Pakistani forces at an alleged al Qaeda safe house in Faisalabad, where US military documents say Barhoumi trained Qahtani and Sharbi to make hand-held remote detonators of a kind later used against US forces in Afghanistan.

REUTERS SHB BST0002