The head of Pentagon intelligence has ordered all US military officials to be more forthcoming in sharing classified information with allies, saying overly restrictive caveats on intelligence reports have hindered America's ability to work with coalition partners.

In a two-page memorandum sent two weeks ago to senior Pentagon officials, Stephen Cambone, undersecretary for intelligence and a close confidant of Donald Rumsfeld, defence chief, said the restrictions on international disclosure - classifying documents as "Not releasable to foreign nationals", or "Noforn" in Pentagon jargon - has been excessive.