German Chancellor Angela Merkel has warned the United States against snooping on her phone calls saying that it is "really not on" for friends to spy on each other.
Merkel demanded an explanation of the claims made by media that the U.S. National Security Agency (NSA) eavesdropped on the personal phone calls of a Western leader, the BBC reports.
Merkel said France and Germany wanted to hold talks with the U.S. to settle the matter.
Other EU leaders also voiced concern about the scale of U.S. surveillance, which threatens to overshadow EU talks on economic growth and migration to the EU.
Earlier, it was revealed that the NSA has been spying on closed discussions inside both the United Nations and the European Union.