The head of the office of the Chancellery, Peter Altmaier, invited Ambassador Emerson to hold "immediate talks" about the latest WikiLeaks revelations, which claim that the US National Security Agency (NSA) had spied on government ministries and cabinet members. The diplomatic request was an invitation, as opposed to the more serious "summons" that can be issued to ambassadors.

Initial reports in the "Frankfurter Allgemeine Zeitung," one of Germany's bestselling broadsheet newspapers, said that the meeting was scheduled to be held on the same day. Altmaier reportedly expected clarification on the tapped phone conversations conducted by Chancellor Merkel and employees of her office.

German Finance Minister Wolfgang Schäuble also criticized the NSA spying campaigns, adding that he too demanded explanations.

"It is becoming increasingly apparent that some of the people working at the American intelligence services might be losing sight of the ends-versus-means debate," Schäuble told the "Bild" Zeitung.

Espionage more far-reaching than previously assumed

According to documents released by WikiLeaks, the NSA spied not only on Chancellor Merkel as had been disclosed in a previous leak in 2013, but also on high-profile politicians. The list included Sigmar Gabriel, now deputy chancellor but leader of the opposition at the time, and other top officials in the finance, economy and agriculture ministries. France has also recently been hit by NSA-spying revelations dating between 2006 and 2012 - impacting on Presidents Jacques Chirac, Nicolas Sarkozy and Francois Hollande.

German Finance Minister Wolfgang Schäuble demands an explanation

The documents highlight 69 telephone numbers which are still in use, indicating that the spying could be ongoing. However, the most recent WikiLeaks data hails from 2011.

British intelligence services were also implicated in the spying revelations. The documents showed that the spying dates back to the 1990s and that the NSA was especially interested in German currency and trade policy. They include a recorded telephone conversation the chancellor had regarding Greece's debt difficulties from October 2011.

Members of the German parliament's investigative committee looking into the NSA demanded consequences for the most recent set of revelations. Martina Renner of the left-wing party "Die Linke" urged the government to disclose important NSA documents immediately. Green Party lawmaker Konstantin von Notz called on the attorney general to launch an investigation.

A previous investigation into NSA spying activities in German government circles had just been closed in June on account of a lack of evidence. It remains unclear whether there may be legal consequences involved, however, the Federal Prosecutor's Office said that this didn't mean that the previous case would be reopened.

ss/msh (AFP, dpa)