With 100 days to go until the royal wedding, Fleet Street is straining to reveal whatever it can about Kate Middleton's dress. How can Buckingham Palace possibly keep the garment hidden until her big day?

There's a secret out there, jealously guarded at the highest level of the British state. A secret that millions are desperate to learn and journalists are scrambling over each other to uncover.

The classified information is not some top-secret intelligence file and it isn't a scientific patent destined to make its inventor wildly rich. It is neither the cure for cancer nor a weapon of mass destruction.

Instead, it is pale-coloured, silky and quite possibly shaped like a meringue. It is a wedding dress, designed for the future Princess Catherine.

As she steps out of her car and makes her way to Westminster Abbey in her final moments as Miss Kate Middleton on 29 April, millions of eyes will be on her gown. Just as with any matrimonial ceremony, the dress will occupy a status within the event's hierarchy only just below that of bride herself.

The prestige of working on such a high-profile design project will, of course, be enough to keep many mouths sealed. But it is unlikely to be enough for palace officials, who can be expected to insist on all concerned signing confidentiality agreements.

However, former BBC royal correspondent Jennie Bond suspects that, even in the Britain of 2011, courtiers have an even more powerful weapon at their disposal: old-fashioned deference.

"They'll use honour," she insists. "You are honoured to be creating the royal dress and in return you are expected to keep your trap shut."

Who, after all, wants to be the cad who spoils a bride's big day? As long as that remains a factor, the monarchy is in with a shout of preserving the country's best-embroidered state secret.

http://www.bbc.co.uk/news/magazine-12207203