The Pentagon warned lawmakers on Tuesday that WikiLeaks’ long-expected release of thousands of classified U.S. diplomatic cables could come as soon as Friday, according to a report from Bloomberg.

The cables “touch on an enormous range of very sensitive foreign policy issues,” according to an e-mail from Assistant Secretary for Legislative Affairs Elizabeth King to the Senate and House Armed Services Committees quoted in the report. “State Department cables by their nature contain everyday analysis and candid assessments that any government engages in as part of effective foreign relations…. The publication of this classified information by WikiLeaks is an irresponsible attempt to wreak havoc and destabilize global security. It potentially jeopardizes lives.”

WikiLeaks responded on Twitter Tuesday night. “The Pentagon is hyperventilating again over fears of being held to account.”

The release has been anticipated since the arrest last spring of Army intelligence analyst Bradley Manning. In online chats with the ex-hacker who ultimately turned him in, Manning described providing WikiLeaks with a massive cache of diplomatic cables. Manning said the cables docuмented years of secret foreign policy and “almost-criminal political back dealings.”

“Hillary Clinton and several thousand diplomats around the world are going to have a heart attack when they wake up one morning, and find an entire repository of classified foreign policy is available, in searchable format, to the public,” Manning told former-hacker Adrian Lamo.

Bradley Manning (Facebook.com)

Wikileaks founder Julian Assange has previously denied receiving the cables, though a cable from the U.S. embassy in Reykjavik, Iceland, appeared on the Wikileaks website in February.

Manning claimed to have leaked 260,00 cables. But he was charged on July 5 with downloading more than 150,000, and with allegedly leaking at least 50 of them to an unauthorized third party.

The cables were widely accessible within the U.S. military under an information-sharing initiative called Net-Centric Diplomacy.

Established in the government’s post-September 11 drive to break down information barriers between agencies, Net-Centric Diplomacy makes a subset of State Department docuмents available on the Secret Internet Protocol Router Network, or SIPRNet, the Pentagon’s global, Secret-level wide area network. SIPRnet is accessible to cleared American military service members and civilian agencies around the world.

To put their cables on SIPRnet, foreign service officers add a special designator to the header: “SIPDIS,” for SIPRnet Distribution. Department rules preclude certain types of communications from being marked SIPDIS, such as sensitive cables between an ambassador and the U.S. Secretary of State or the White House. Cables containing personally identifying information, such as Social Security numbers, and cables describing department personnel issues would also be omitted.

Though the leaked cables wouldn’t include the most sensitive communiqués between diplomatic posts and Washington, nearly all State Department “reporting cables” carry the SIPDIS designator, and most of those are classified at the Secret or Confidential level, says a former State Department official.

The Reykjavik cable that Wikileaks published is an example of a reporting cable. The cable, dated January 13, memorialized meetings between U.S. and Icelandic government officials over that country’s Icesave banking scandal. The cable revealed that Iceland’s ambassador to Washington, Hjálmar W. Hannesson, had told Washington officials that Iceland’s president was considered “unpredictable.” The unpolitic remark raised eyebrows in Reykjavik.

Manning described that single leak as a “test.” The full database, he wrote, would have significant impact.

“Everywhere there’s a U.S. post, there’s a diplomatic scandal that will be revealed,” he wrote. “It’s open diplomacy. World-wide anarchy in CSV format. It’s Climategate with a global scope, and breathtaking depth. It’s beautiful, and horrifying.”

With reporting by Kim Zetter. Top image: Wikileaks founder Julian Assange takes his seat during a press conference in Geneva, Switzerland, Thursday, Nov. 4, 2010. (AP Photo/Keystone, Martial Trezzini)