A programme devised by British intelligence allowed analysts to monitor the bookings of foreign diplomats at 350 top hotels across the world, according to documents leaked by the whistleblower Edward Snowden.

The German news magazine Der Spiegel reported on Sunday that the automated system alerted the UK's eavesdropping centre, GCHQ, to the timings and locations of diplomats' travel arrangements.

The papers make clear that these details allowed the "technical operations community" to make necessary preparations before the visits, the magazine said, suggesting that the diplomats' rooms would be monitored or bugged.

The GCHQ programme, called Royal Concierge, was first trialled in 2010 and has been in operation since then, the papers reveal.

The programme worked by intercepting reservation confirmations when they were sent to government addresses from any of the 350 monitored hotels, said Spiegel online.

The papers did not name any hotels or diplomats who had been spied upon, though unnamed hotels in Zurich and Singapore were cited as examples.

Separate documents seen by Spiegel listed the potential capabilities for monitoring a hotel room, which included wiretapping the telephone and fax machine as well as monitoring computers hooked up to the hotel network.

According to Spiegel, one of the presentations describing Royal Concierge was entitled Tales from the Wild, Wild West of GCHQ Operational Data-Mining.

GCHQ said it would not confirm or deny the story, which is the latest to emerge from the cache of documents leaked by Snowden this year.