Washington: A leak from the White House or US spy agencies about a video from Osama bin Laden sabotaged a private intelligence firm's secret ability to intercept Al-Qaeda communications, the Washington Post reported today.

The Post said that SITE Intelligence Group had covertly developed access over several years to Al-Qaeda's communications network but that the access was lost after the administration of President George W Bush let out that the company had obtained the bin Laden video early last month ahead of its official release.

"Techniques that took years to develop are now ineffective and worthless," SITE founder Rita Katz told the Post. SITE monitors websites and public communications linked to radical Islamist groups and organisations deemed terrorist by US authorities and provides the information to clients, including news media companies.

It got hold of the bin Laden video before its release and provided it for free to the White House on the morning of September 7. SITE had insisted that the video's existence remain secret to protect its own work.

By the afternoon, however, the video and a transcript from it had been leaked by someone in the Bush administration to a cable television news network and broadcast worldwide, the Post reported.

According to Katz, this tipped off al-Qaeda that its communications security had been breached by SITE. The Post said administration officials asked about the SITE account of the leak did not dispute it.