Washington, Oct 21 (IANS) For months during Bill Clinton's administration, the White House lost the card with a set of numbers for opening the briefcase containing codes for a nuclear attack, a former military officer says.

Gen Hugh Shelton, who was Chairman of the Joint Chiefs of Staff at the time, said in his new memoir, "Without Hesitation: The Odyssey of an American Warrior", that "the codes were actually missing for months. That's a big deal -- a gargantuan deal", said The Telegraph newspaper.

A similar claim was made by Lt Col Robert Patterson, a former aide, in a book published seven years ago.

He was one of the men who carried the briefcase, known as the "football", and he said the morning after the Monica Lewinsky scandal broke that he made a routine request of the president to present the card so that he could provide an updated version.

"He thought he just placed them upstairs," Lt Col Patterson recalled.

"We called upstairs, we started a search around the White House for the codes, and he finally confessed he in fact misplaced them. He couldn't recall when he had last seen them."

The daily quoted him as saying that the president lost the card holding the codes, known as the biscuit, in 1998. But according to Gen Shelton, the card went missing in 2000.

Former president Jimmy Carter was rumoured to have once left the "biscuit" in a suit that was sent to the dry cleaners.