German politicians have demanded an apology from US President Barack Obama over reports that the National Security Agency (NSA) was tapping Chancellor Angela Merkel’s mobile phone for over a decade. “We will not allow ourselves to be treated by the Americans in this manner. Spying on friends and partners is completely unacceptable,” German Interior Minister Hans-Peter Friedrich said on Sunday. Germany expected an apology from the US and an assurance that its surveillance operations will be stopped immediately, he said in a TV interview.