German Chancellor Angela Merkel, angry at revelations that the US snooped on her, will discuss covert US surveillance in Europe with French President Francois Hollande Thursday, a French diplomatic source said.
Merkel and Hollande, due to meet on the margins of an EU leaders' summit overshadowed by the growing scandal, "will also obviously discuss it and how to coordinate their response," a French diplomatic source said.
Earlier Thursday, the German government summoned the US ambassador to Berlin over reports Washington had monitored Merkel's mobile phone, sparking outrage from the chancellor.
Merkel called US President Barack Obama Wednesday to warn that if correct, the invasive snooping would amount to a "breach of trust" between international partners.
Merkel made clear to Obama that "she unequivocally disapproves of such practices, should they be confirmed, and regards them as completely unacceptable," according to a German government statement.
The chancellor also demanded "an immediate and comprehensive explanation" from Washington, it said.
"Among close friends and partners, as the Federal Republic of Germany and the US have been for decades, there should be no such monitoring of the communications of a head of government," it added.
The White House said in response that the US is not now listening in on Merkel, but did not deny the possibility her communications may have been intercepted in the past.
Earlier this week, Washington branded as inaccurate reports that it had spied on millions of French citizens, but Hollande has pressed for EU leaders to take up the issue as part of wider efforts on data protection in the 28-member bloc.
The revelations of US spying on friends, allies and adversaries around the world sourced to whistle-blower Edward Snowden have led to a series of rows with Washington.
French President Francois Hollande's spokeswoman Najat Vallaud-Belkacem said Wednesday that Paris and Washington had agreed to work on new "bilateral cooperation between the French and American intelligence agencies" in the wake of the scandal.