WASHINGTON - A LEADING US rights group on Thursday slammed Defence Secretary Robert Gates for not backing President Barack Obama's executive order to halt proceedings against terror suspects at Guantanamo Bay.

'Despite President Obama's orders to close Guantanamo and halt proceedings, it appears this has not filtered down through the Department of Defence,' said Anthony Romero, head of the American Civil Liberties Union (ACLU).

'Secretary Gates has not stepped in to enforce the promise Obama made to halt all military commission proceedings. This raises questions about the credibility of Gates to strike a new path and be able to respond to the instructions of his new commander in chief,' said Mr Romero.

Within days of taking office, Mr Obama had ordered the closure of the prison at the US naval base in Guantanamo Bay, Cuba within a year and requested a halt to military commission proceedings at the facility.

But a military judge at Guantanamo rejected the new administration's request to suspend the trial of Saudi national Abd al-Rahim al-Nashiri, accused of participating in the 2000 attack on the USS Cole.

Al-Hashiri is due to be arraigned on Monday.

'Certainly Secretary Gates has the ability to put a halt to these proceedings,' Mr Romero told a press conference.

'One must question whether this is just the right hand not knowing what the left hand is doing, whether this is a revolt in the new Obama administration, or whether the new Secretary Gates is just like the old Secretary Gates,' he said.

Mr Gates served as defence secretary under president George W. Bush and was retained in the post by Mr Obama. -- AFP