Furious German officials said Wednesday that U.S. intelligence agencies may have been monitoring German Chancellor Angela Merkel’s cellphone, and the German leader spoke to President Obama on Wednesday about the issue, according to her spokesman.

Merkel told Obama that, if the accusations are confirmed, she “unequivocally disapproves of such practices and sees them as completely unacceptable,” her spokesman, Steffen Seibert, said in a highly unusual late-night statement.