Screenshot of the Guardian's book about WikiLeaks via Google Books.

WikiLeaks says it has opened "pre-litigation action" against the Guardian, a British newspaper, for "negligently" disclosing a password that allegedly led to the release of unredacted copies of more than 100,000 U.S. State Department files in recent days, according to an editorial posted to the WikiLeaks website early Thursday (British time).

The newspaper denied the allegations in an article posted on its website, saying in a statement, "It's nonsense to suggest the Guardian's WikiLeaks book has compromised security in any way."

The Guardian's book about WikiLeaks and its founder, Julian Assange, was published in February. The password -- ACollectionOfHistorySince_1966_ToThe_PresentDay# -- is mentioned on page 139 in a section about Assange explaining to David Leigh, the book's co-author and a Guardian editor, how to access the government files in secure online location. Leigh wrote that Assange also noted to add the word "Dipolmatic" before "History" in the password. An explanation of where to enter the password was not included.

The Guardian said Thursday that it was told at the time that the password would expire within hours.

"It was a meaningless piece of information to anyone except the person(s) who created the database," the Guardian stated. "No concerns were expressed when the book was published and if anyone at WikiLeaks had thought this compromised security they have had seven months to remove the files. That they didn't do so clearly shows the problem was not caused by the Guardian's book."

WikiLeaks tipped off the State Department a week ago to the fact that a password had been compromised and the release of unredacted files would be imminent. The Guardian reported that the original file also was uploaded to BitTorrent last year, which the Guardian did not have any knowledge about.

The most recent release of unredacted files includes the name of 100 foreign diplomats that had been marked to be kept secret, the New York Times reported. One of those files also said U.S. troops executed at least 10 Iraqi civilians in a 2006 incident.

Mainstream media coverage of WikiLeaks has declined in recent weeks despite a constant flow of document releases. WikiLeaks' editorial said 50 media and human rights organizations are helping comb through documents and redact sensitive names. WikiLeaks has already severed ties with the Guardian and the New York Times for failure to follow the organization's instructions.

Assange remains on house arrest while he awaits a court ruling on whether he should be extradited to Sweden.

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