Britain's worst-kept secret is finally out: Prince William and Kate Middleton are to marry.

Reports say that when Prime Minister David Cameron announced the engagement at a cabinet meeting, the room erupted in loud thumping and cheers. The Britons love their royals, and the news that a commoner such as Kate can become Queen is the stuff of literary fantasy and Hollywood scripts.

Sadly, though, whatever chance Miss Middleton had of living a normal life since she began dating the second-in-line to the throne, has now finally evaporated.

The challenge for the couple will be to try and plan the rest of their lives together while under the intrusive glare of the British paparazzi. The pressures of living under the lens can destroy any relationship, and the sad chapter of Diana's life under scrutiny destroyed her marriage with Prince Charles.

The couple need their privacy as much as possible. But congratulations.