A report in Tuesday's edition of the London-based Independent newspaper claimed that documents from the U.S. National Security Agency together with aerial photos and information about past spying activities in Germany suggested Britain could be operating a spy station using equipment housed on the embassy roof.
The ministry said in a statement that Britain's ambassador was "invited in" at the behest of German Foreign Minister Guido Westerwelle.
The head of the ministry's European department noted that "eavesdropping on communication from diplomatic premises would be against international law," the statement added.
The embassy refused to comment on the newspaper report. Britain's Foreign Office confirmed the ambassador attended a meeting at the Ministry of Foreign Affairs on the invitation from a senior official. It declined to comment further.
In diplomatic terms, the invitation was a step below last month's summoning of the U.S. ambassador in Berlin following allegations that American intelligence may have targeted Chancellor Angela Merkel's cellphone.
Government officials reacted with outrage to the report, published by German news weekly Der Spiegel and citing documents obtained through NSA leaker Edward Snowden.
German officials have since been dispatched to Washington to find out exactly what surveillance the U.S.
A spokeswoman for Germany's domestic intelligence agency said Tuesday that a group it set up after the first NSA spying allegations emerged in the summer is looking at the activities of British as well as U.S. intelligence. She did not comment on any results, which go to a parliamentary committee.
She spoke on condition of anonymity because the rules of her job did not allow her to be named.