WASHINGTON — Former United States President Bill Clinton is calling for clarity in how countries gather intelligence.

And when it comes to secretly monitoring the telephone conversations or emails of world leaders, Mr Clinton says that during his presidency it depended on who the leaders were. He says American agencies might have spied on leaders his administration thought were engaging in hostile acts against the US.

He says his administration did not have the ability to do a lot of what’s currently being done.

Documents leaked this summer by former National Security Agency (NSA) contractor Edward Snowden exposed a massive US surveillance operation that covered telephone records, email traffic and the communications of US allies, including Brazil, Germany and Mexico.

A report by a panel of advisers President Barack Obama chose to review NSA programmes is expected this month. AP