Spies listened to Clinton's call

German sources say the interception of the phone calls was only done "by accident". Photo / AP

German secret agents intercepted one of Hillary Clinton's telephone calls while she was the US Secretary of State and also listened in to a call by John Kerry, her successor, it emerged this weekend.

The disclosure is an embarrassing reversal of the spying scandal that blew up when it was revealed last year that America bugged Chancellor Angela Merkel's mobile telephone.

Clinton was on a US government plane when German intelligence services overheard her call and, against their own internal protocol, stored it, intelligence sources told German media.

The intercepted call took place in 2012 between Clinton and Kofi Annan, the former United Nations Secretary-General, who had just returned from negotiations in Syria and wanted to brief her, the German weekly Der Spiegel reported.

Der Spiegel said agents from the state intelligence services last year listened in on a phone call by Kerry, the current US Secretary of State, as he discussed growing tensions in the Middle East with an unknown figure.

The newspaper also claimed Germany has been spying on Turkey, its Nato ally, since 2009.

German intelligence sources have tried to minimise the impact of the revelations by explaining the interception of the phone calls of both secretaries of state was only done "by accident".

The secret agents had not meant to hear Clinton's call or to keep the recording of it, according to a joint media investigation published by Suddeutsche Zeitung and NDR and WDR, two German regional public broadcasting outlets.

A source told the outlets the fact the recording of the call had not been immediately destroyed, as is routinely done if allies' phone calls are picked up by accident, was "idiocy".