One military network cut off from cables

WASHINGTON (Reuters) - The State Department has cut off a U.S. military computer network from its database of diplomatic cables after WikiLeaks obtained more than 250,000 such cables, a senior U.S. official said on Tuesday.

The official, who spoke on condition of anonymity, said the system was the U.S. military's Secret Internet Protocol Router Network, known as SIPRNet, believed to have been the ultimate source for the cables obtained by the whistleblower website.

The disclosure of the cables on Sunday by five media groups has been a severe embarrassment to the U.S. government because they describe the inner workings of U.S. diplomacy and contain candid, critical assessments of foreign leaders.

Secretary of State Hillary Clinton on Monday voiced regret over the release of the classified information and she has spent much of the last week reaching out to foreign officials to try to limit damage from the disclosures.

Among the nuggets in the cables were reports that Saudi King Abdullah repeatedly urged the United States to attack Iran and destroy its nuclear program.

U.S. officials have repeatedly said that maintaining the confidentiality of their dealings with foreign governments is vital to ensure people keep talking to them.

But Defense Secretary Robert Gates sought to play down the significance of the leaks.

"Is this embarrassing? Yes. Is it awkward? Yes. Consequences for U.S. foreign policy? I think fairly modest," Gates told reporters at the Pentagon.

"The fact is governments deal with the United States because it is in their interests, not because they like us, not because they trust us and not because they believe we can keep secrets," he said.

"Some governments deal with us because they fear us, some because they respect us, most because they need us."

The U.S. investigation of the leaks has focused on Bradley Manning, a former U.S. Army intelligence analyst in Iraq. He is under arrest, charged with leaking a classified video showing a 2007 helicopter attack that killed a dozen people in Iraq, including two Reuters journalists.

According to the military charge sheet against him, Manning is accused of obtaining "more than 150,000 diplomatic cables." U.S. officials declined to say whether those cables were the same ones obtained by WikiLeaks and the media groups.

U.S. officials have been at pains to avoid directly linking Manning to WikiLeaks and refuse to discuss the case, citing the official investigation. The whistleblowing website itself does not appear in the charge sheet provided to the public.

In an Internet chat, Manning said he would come into work with music on a recordable CD labeled "something like Lady Gaga" then erase the music and download the data from SIPRNet.

(Additional reporting by Phil Stewart; Editing by John O'Callaghan)