The head of the powerful Senate Intelligence Committee in the United States is calling for a major review of the country's spying operations after its chairwoman said she had not been satisfactorily informed.
Senator Diane Feinstein said she is totally opposed to the gathering of intelligence on any US allies and it is wrong that President Barack Obama did not know about the surveillance of foreign leaders.
Ms Feinstein's comments came as the White House defended American intelligence gathering programmes in Europe.
Pressure is growing on the White House to explain why Mr Obama apparently didn't know about the extent of the National Security Agency's spying operation. It appears until this northern hemisphere summer he wasn't aware that they were tapping the phones of one of his closest allies, Germany's Chancellor Angela Merkel, the BBC reports.
The White House refuses to discuss the specifics of its intelligence gathering - specifics which are now often splashed across the world's newspapers.
But Mr Obama's spokesperson Jay Carney said that a balance had to be struck. He said additional constraints on intelligence gathering might arise from the review that Mr Obama had ordered.
Diane Feinstein said all surveillance of leaders of countries friendly to the US should stop. She said the White House has told her it will, but a senior administration official told the BBC this is not accurate.
New Zealand Prime Minister John Key says he is confident that he has not been spied upon by the US.
