- Agency given more than 200 numbers by government official
- NSA encourages departments to share their 'Rolodexes'
- Surveillance produced 'little intelligence', memo acknowledges
The National Security Agency monitored the phone conversations of 35 world leaders after being given the numbers by an official in another US government department, according to a classified document provided by whistleblower Edward Snowden.
The confidential memo reveals that the NSA encourages senior officials in its "customer" departments, such the White House, State and the Pentagon, to share their "Rolodexes" so the agency can add the phone numbers of leading foreign politicians to their surveillance systems.