Sir John Sawers is due to take over as head of the Secret Intelligence Service in November. The SIS, popularly known as MI6, is Britain's global intelligence-gathering organization.

In what the Mail on Sunday called an "extraordinary lapse," the new spy chief's wife, Lady Shelley Sawers, posted family pictures and exposed details of where the couple live and take their holidays and who their friends and relatives are.

The details could be viewed by any of the many millions of Facebook users around the world, but were swiftly removed once authorities were alerted by the newspaper's enquiries.

It was the latest in a string of security blunders, lapses and leaks by British officials that have embarrassed the government of embattled Prime Minister Gordon Brown.