The United States is warning some foreign intelligence services that documents obtained by Edward Snowden contain details of how they cooperate secretly with Washington, a newspaper said Thursday.
The Washington Post said some of the tens of thousands of documents harvested by the fugitive former intelligence contractor contain sensitive material about collection programs against countries such as Iran, Russia and China.
The paper quoted unnamed US administration officials.
The notification coincides with a global uproar over US surveillance of allied countries and their leaders, the latest being German Chancellor Angela Merkel.
The process of advising other countries is being handled by the Office of the Director of National Intelligence, the Post said.
In one case, Snowden documents have information about a program operated from a NATO member country against Russia and which gives valuable intelligence to the US Air Force and Navy, the paper reported.
"If the Russians knew about it, it wouldn't be hard for them to take appropriate measures to put a stop to it," it quoted one US official as saying.