The White House has instructed every US government department and agency to create "insider threat" programmes that will ferret out disgruntled or untrustworthy employees who might be tempted to leak the sort of state secrets recently made public by the website WikiLeaks.

A 13-page memo detailing the new policy urges senior civil servants to beef up cyber security and hire teams of psychiatrists and sociologists who can "detect behavioural changes". They will then monitor the moods and attitudes of staff who are allowed to access classified information.

The move is designed to prevent further embarrassing disclosures of the sort which have dominated the news in recent months. Unfortunately, just 48 hours after the memo was sent, a copy was leaked to staff at NBC news, who duly posted it on their website.

"Do you have an insider threat programme or the foundation for such a programme?" it asks department heads, adding that they should keep a close eye on the "relative happiness" of workers, because a staffer who displays "despondence and grumpiness" is likely to be untrustworthy.

In a passage which recalls a level of paranoia last seen during the Cold War, it asks whether agencies are using lie-detector tests or are trying to identify "unusually high occurrences of foreign travel, contacts, or foreign preference" by members of their staff.

The author of the leaked document, Jacob J Lew, is the director of the White House Office of Management and Budget. He seems particularly anxious to prevent the media from getting its hands on embarrassing information.

"Are all employees required to report their contacts with the media?" the memo asks, suggesting that staff should even be monitored once they leave the Civil Service: "Do you capture evidence of pre-employment and/or post-employment activities or participation in online media data mining sites like WikiLeaks or Open Leaks?"

The dump of diplomatic cables which ended up in the hands of WikiLeaks is believed to have been the work of Bradley Manning, a relatively junior soldier who nonetheless had access to the computer network used by the US Department of Defense and Department of State to transmit classified information.

Mr Manning, currently in military custody awaiting a court martial, is believed to have been motivated by his experiences in Iraq, which left him disillusioned with US foreign policy. Investigators believe his state of mind was also affected by a series of personal upheavals. He had recently been demoted, and was upset after splitting up with a girlfriend.

The documents Mr Manning allegedly passed to WikiLeaks were hugely embarrassing to the US. Yet he was just one of hundreds of thousands of troops and civil servants with security clearance to access them.

Judging by the contents of his memo, Mr Lew believes further leaks can be prevented by senior staff keeping a closer eye on their employees. However, many security experts who have seen his memo disagree. "This is paranoia, not security," Steven Aftergood, a national security specialist for the Federation of American Scientists, told NBC. "It may be that this is what the administration needs to do to deflect congressional anger [over WikiLeaks], but some of it doesn't make any sense."