Banned procedures include forced nakedness, hooding and threatening prisoners with dogs

Delayed more than a year amid criticism of the defence department's treatment of prisoners, the revised Army Field Manual released on Wednesday updates a 1992 version.

It also explicitly bans beating prisoners, sexually humiliating them, depriving them of food or water, performing mock executions, shocking them with electricity, burning them, causing other pain and a technique called "water boarding" that simulates drowning, said Lt. Gen. John Kimmons, army deputy chief of staff for intelligence.

Officials said the revisions are based on lessons learned since the US began taking prisoners in response to the September 11 attacks on the United States.

Release of the manual came amid a flurry of announcements about US handling of prisoners, which has drawn criticism from Bush administration critics as well as domestic and international allies.

President George W Bush acknowledged the existence of previously secret CIA prisons around the world where terrorist suspects have been held and interrogated, saying 14 such al-Qaeda leaders had been transferred to the US military prison at Guantanamo Bay and will be brought to trial.

Secret section

Though defense officials earlier this year debated writing a classified section of the manual to keep some interrogation procedures a secret from potential enemies, Kimmons said that there was no secret section to the new manual.

Bush decided shortly after the September 11 attacks that since it was not a conventional war, "unlawful enemy combatants" captured in the fight against al-Qaeda would not be considered prisoners of war and thus would not be afforded the protections of the Geneva convention.

The new manual, called "Human Intelligence Collector Operations," applies to all the armed services, not just the army.

However, it does not cover the Central Intelligence Agency, which has also come under investigation for mistreatment of prisoners in Iraq and Afghanistan and for keeping suspects in secret prisons elsewhere around the world since the September 11 attacks.