PRINCE WILLIAM and Prince Harry defied advice from their royal protection officers to stop using their mobile telephones as suspicions grew that their messages were being intercepted.

The princes were given the same uncompromising message as senior Cabinet ministers that their mobile telephones were no longer secure, were susceptible to being bugged, and should be used only sparingly.

As The Times disclosed yesterday, the police inquiry has been widened from Clarence House to cover politicians such as Tessa Jowell, the Culture Secretary, after the News of World reported that she had accused her husband David Mills, a businessman facing fraud charges in Italy, of cashing in on her links to the Prime Minister.

Scotland Yard was called in last November to investigate complaints that three key officials at Clarence House, who liaise daily with the princes, had been targeted by hackers.

But in the ensuing months the princes continued to use their telephones, with some of their text messages to their girlfriends being reprinted in the News of the World.

The Prince of Wales is protected from eavesdropping operations. He — as well as the Prime Minister, the Foreign Secretary and the Defence Secretary — has a secure telephone system. The Prince can be contacted on it in any part of the world from Clarence House. “It’s watertight,” a source said last night. The Duchess of Cornwall has the same security back-up.

The Prince, who has been kept informed of the police inquiry, is particularly sensitive about telephone security. In 1998 a newspaper published the “Camillagate” tape revealing an intimate conversation he had with Mrs Parker Bowles, as the Duchess was then.

Neither William nor Harry will have to give evidence in a court case because it was not their telephone voicemail systems that were allegedly downloaded. It was after two stories appeared in the News of the World about William, including details known to only three officials, that supicion grew that telephone calls or messages were being intercepted.

The principal players will be Paddy Harverson, the Clarence House communications secretary; Jamie Lowther-Pinkerton, the former SAS officer who is private secretary to the princes and Helen Anstey, William’s diary secretary.

Clarence House said that it could make no comment on the police investigation.

The police inquiry, under the Regulation of Investigatory Powers Act, was triggered by the complaint from the three officials to the royal protection officers. Breaches of the Act are punishable by up to two years in prison or unlimited fines.

The Anti-Terrorist Branch is leading the inquiry because of the security implications involving such senior members of the Royal Family and the Government.

The police are examining whether David Blunkett, the former Home Secretary, was targeted by eavesdroppers over his alleged affair with an estate agent last year, as reported in the press.

Sven-Göran Eriksson, the former England football head coach, stopped using his mobile telephone months ago because of fears that it was being hacked into.

Clive Goodman, 48, from Putney, South London, the royal editor of the News of the World, and Glenn Mulcaire, 35, a former Wimbledon footballer who runs a crisis management company, have been charged with offences of plotting to intercept communciatons.

They have been bailed to appear at Horseferry Road Magistrates’ Court next Wednesday. A 50-year-old man was released on bail on Wednesday.

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