Guards have confiscated a Lord of the Rings movie screenplay from a Canadian awaiting trial at Guantanamo, his lawyer and U.S. officials said Thursday.

Navy Lt.-Cmdr. William Kuebler, the military-appointed lawyer for Omar Khadr, told reporters he gave the detainee the script to build trust.

In addition to seizing the screenplay, the military said he could no longer play dominoes and chess during visits with Khadr, who was 15 when he was captured by the U.S. military after a firefight in Afghanistan in 2002. Khadr is accused of throwing a grenade that killed an American soldier during the firefight.

Kuebler said the games and the screenplay are essential to his ability to defend his client: "There is an enormous challenge to building a rapport."

Guantanamo officials issued a statement that guards found the screenplay along with other unapproved items, including news articles from the internet, mixed with legal papers that the prisoner is allowed to keep.

"The Lord of the Rings screenplay has been returned to … Kuebler as a violation of the prohibition against providing detainees materials that are not directly related to his representation of his client," the military said.

A spokesman for the detention centre, army Lt.-Col. Ed Bush, said all three instalments of the book version of J.R.R. Tolkien's Lord of the Rings trilogy are available to prisoners.

It was not clear why Khadr, now 21, wanted the screenplay. Some detainees have complained through their lawyers about long waits for books from Guantanamo's library.

The United States holds about 275 men at Guantanamo on suspicion of terrorism or links to al-Qaeda and the Taliban, and has said it plans to prosecute about 80 before a special war crimes tribunal.