The German magazine Der Spiegel says the British intelligence agency GCHQ monitors bookings of at least 350 luxury hotels around the world to automatically track foreign diplomats and government officials who might be staying there.

The magazine cites documents provided by NSA leaker Edward Snowden that showed GCHQ began its “Royal Concierge” program more than three years ago.

It says knowledge of where diplomats will stay allows GCHQ to prepare eavesdropping measures on what the agency terms “governmental hard targets.” Plans to extend the system to cover car rentals also are mentioned.

Der Spiegel has repeatedly reported from Snowden’s trove of NSA documents, and the article published Sunday was co-written by his confidante Laura Poitras.

GCHQ declined to comment on the report.

(AP)