Germany is high on the list of telephone telecommunication and Internet message tapping, as half a billion phone calls, emails and Internet chat messages could be intercepted by U.S. intelligence monthly on average, German magazine Der Spiegel reported on Sunday.

Citing classified documents disclosed by fugitive former National Security Agency contractor Edward Snowden, it showed that Germany belonged to the "third-class" rank under U.S. intelligence surveillance, the highest in all of the EU member countries and are subject to deliberate attack of the signal.

It is revealed that the National Security Agency (NSA) put some 20 million phone calls and roughly 10 million internet data connections in Germany under its close monitoring practice every day under normal circumstance, while it could rocket up to 60 million phone calls under extreme condition, according to the report.

The U.S. intelligence would eventually store the metadata, or the connections at its headquarters, not necessarily the content of these monitored phone calls, text messages, emails and internet chat.

The much higher frequency of monitoring in Germany has caught many Germans by big surprises, as in contrast to France where some 2 million long distance connection data are reportedly under surveillance by NSA per day, it was 10 times less than in Germany, while Canada, Australia, Britain and New Zealand just remain free of such spying surveillance.

Expressing her frustration, Germany's Justice Minister Leutheusser-Schnarrenberger demands immediate and extensive explanations from the United States, calling it was "beyond our imagination that our friends in the U.S. consider the Europeans as enemies, and hardly able to be explained using the argument of fighting terrorism."