Anger is mounting in Brussels at new revelations about the extent of US spying on European Union countries - with claims that snoops installed bugs inside EU buildings.
The damaging allegations are revealed in new top secret documents leaked by fugitive spy Edward Snowden and seen by German magazine, Spiegel.
The most chilling claim in the secret report from 2010 is that Brussels was subjected to a cyber-attack at its offices in New York and Washington, which was later traced back to a Nato building used by US officials.
Papers suggest US spies eavesdropped on European diplomats in EU buildings in central Washington DC. Computers were also hacked so the United States had access to computer files and emails, reports Spiegel.
The latest disclosures come after a giant spying operation against the EU was revealed, in which Germany was the most heavily spied upon country in Europe by Amercia's National Security Agency (NSA), using its top-secret Prism programme.
If substantiated, the allegations will further damage relations between the EU and the United States that have already been shaken by documents leaked by fugitive spy Edward Snowden. Throughout, the European Union is referred to as a "target".
A top EU official branded the activity "disgusting".
Luxembourg Foreign Minister Jean Asselborn fumed, "If these reports are true, it's disgusting. The United States would be better off monitoring its secret services rather than its allies."
Head of the European Parliament Martin Schultz said, "On behalf of the European Parliament, I demand full clarification and require further information speedily from the US authorities with regard to these allegations."
Documents show German interests were spied on roughly as much as those of China - which is as much a supposed rival of the United States as the European Union is an ally.
Britain and Italy were also high on the list of European member nations whose data was scooped up by Prism.
Of significantly less interest to American agents were three of the so called 'PIGS' - countries whose faltering economies threatened to sink the Euro currency. Portugal, the Republic of Ireland and Greece all had less data gathered by Prism.