Britain’s spies have a top secret programme code-named “royal concierge” that monitors luxury hotel bookings made by foreign diplomats or other targets for espionage.

Leaked documents from Edward Snowden, the former US intelligence contractor, disclose the spy programme and its logo depicting a penguin wearing a crown, a purple cape and holding a magic wand.

“Royal concierge identifies potential diplomatic reservations”, said the secret document, at 350 luxurious hotels around the world automatically informing the Government Communications Headquarters, or GCHQ.

“When diplomats travel to international summits, consultations and negotiations on behalf of governments, they generally tend to spend the night at high-end hotels,” the German magazine Der Spiegel reported.

“When they check-in, in addition to a comfortable room, they sometimes get a very unique form of room service that they did not order: a thorough monitoring by GCHQ.”

British intelligence appears to be conscious of the controversial nature of the clandestine operations with one of the leaked presentations describing the programme titled “Tales from the wild, wild west of GCHQ Operational data-mining”.

Whenever a reservation confirmation is emailed from a targeted hotel to a government email address domain, a daily alert or “tip-off” is sent to GCHQ analysts allowing the “technical operations community” to make the necessary preparations. The documents seen by the magazine do not include the hotel names but give anonymised examples of hotels in Zurich and Singapore.

The three-year-old programme, which was extended after being assessed as successful, gives GCHQ time to set up the monitoring by wiretapping the hotel room’s telephone and fax machine, gaining access to computers hooked up to the hotel network, or eavesdropping on the diplomat in the hotel bar.

Diplomats on confidential missions of high interest are singled out for “technical attack” by elite “active approach teams” of GCHQ hackers with “specialist technologies designed to bridge the gaps to communications that our conventional accesses cannot reach” allowing them to meet “often unique requirements”.

In cases identified as “governmental hard targets” then “human intelligence” operations are organised by GCHQ, involving traditional spies trying to get physically close to diplomats, either by eavesdropping in the bar or striking up an acquaintance, to plant bugs or to gather information directly.

The documents did not disclose how often or what level of operations were carried out by GCHQ following “royal concierge” tracking alerts and GCHQ “neither confirmed nor denied the allegation”.

Earlier this month, the heads of the foreign spy agency MI6, the domestic intelligence service MI5 and GCHQ warned that al-Qaeda and other enemies were “lapping up” intelligence revelations by Mr Snowden and using them to change the way they operate.

The leaks have also strained relations with traditional allies of Britain.

Two weeks ago Germany’s foreign ministry summoned Britain’s ambassador leaked documents showing that GCHQ was operating a secret listening post from the British embassy in Berlin.