Germany "invited in" the British ambassador following reports that the Berlin embassy was being used as a spying post.

Reports in today's Independent newspaper claimed that US National Security Agency documents and aerial photos suggested Britain could be operating a spy station on the embassy roof.

German Foreign Minister Guido Westerwelle asked the ambassador to respond to the report.

The Foreign Ministry said: "Eavesdropping on communication from diplomatic premises would be against international law."

The embassy is sited near the German parliament and Chancellor Angela Merkel's offices.

An embassy spokeswoman said: "We can confirm that meeting has taken place but we are not commenting on anything else to do with this at all."

The Independent claimed a US listening "nest" atop the embassy was shut down last week as NSA spooks tried to limit the damage caused by revelations they had tapped Ms Merkel's mobile phone.

British Prime Minister David Cameron's spokesman insisted that the PM had an "excellent" relationship with Ms Merkel that he expected "will continue."

The spokesman also said ambassador Simon McDonald had been "invited" - a diplomatic step down from the US ambassador's "summoning" over the phone allegations.

At the end of a European Council summit overshadowed by NSA snooping claims last month Mr Cameron refused to be drawn on whether British spy agency GCHQ snooped on European "allies," merely saying it operated within a proper legal framework.

German officials have been dispatched to Washington to seek a "no-spy" agreement with the US.