35 world leaders 'had their phones monitored by US spies'

At least 35 world leaders had their phones monitored by US spies, it has been claimed, an escalating diplomatic row between Europe and America

The White House told The Telegraph the US had never monitored David Cameron's communications but would not give the same assurance about other leaders  Photo: GETTY IMAGES

Hours after Angela Merkel confronted President Barack Obama over allegations that her personal mobile had been tapped, new documents showed that US surveillance extended to dozens of other heads of government.

The National Security Agency (NSA) encouraged other US government departments to share their "rolodexes" of foreign contacts which were then targeted.

"Such 'rolodexes' may contain contact information for foreign political or military leaders, to include direct line, fax, residence and cellular numbers," according to one document given to The Guardian by Edward Snowden, the fugitive leaker.

The White House told The Telegraph the US had never monitored David Cameron's communications but would not give the same assurance about other leaders.

"We are not going to comment publicly on every specific alleged intelligence activity," said Caitlin Hayden, a White House spokesman.