The White House informed a leading Democratic lawmaker, Senator Dianne Feinstein of California, of its plans, which grew out of a broader internal review of intelligence-gathering methods, prompted by the leak of N.S.A. documents by a former contractor, Edward J. Snowden.
In a statement on Monday, Ms. Feinstein, chairwoman of the Senate Intelligence Committee, said, “I do not believe the United States should be collecting phone calls or emails of friendly presidents and prime ministers.” Ms. Feinstein, who has been a stalwart defender of the administration’s surveillance policies, said her committee would begin a “major review of all intelligence collection programs.”
The White House said Monday evening that no final decision had been made on the monitoring of friendly foreign leaders. But the disclosure that it is moving to prohibit it signals a landmark shift for the N.S.A., which has had nearly unfettered powers to collect data on tens of millions of people around the world, from ordinary citizens to heads of state, including the leaders of Brazil and Mexico.
It is also likely to prompt a fierce debate on what constitutes an American ally. Prohibiting eavesdropping on Ms. Merkel’s phone is an easier judgment than, for example, collecting intelligence on the military-backed leaders in Egypt.
