Prince William has come under fire over an estimated annual bill of £1.4 million which the British government has to foot to protect him at a private cottage after he shunned the Royal Air Force accommodation, a media report said. The Prince is classified as the highest security risk and receives round-the-clock armed protection. Scotland Yard provides him with a number of personal protection officers. In addition, a 15-strong unit of armed officers has been formed by North Wales Police to look after him during his training. But, the second-in-line to the British throne's decision to live off base for the duration of his three-year helicopter pilot training course at RAF Valley in Anglesey has costly implications for the force providing his security, the 'Daily Express' reported. The new arrangement means North Wales will lose 15 frontline officers, unless additional funds can be found to replace them. Each one is estimated to cost around £70,000 in pay, pension and training, the report said. Former officers estimated the unit's overall cost will be £1.4 pounds for each of the three years of William's RAF training. Anti-monarchy campaign group Republic has slammed the move. Spokesman, Mr Graham Smith, said: "This is an appalling waste of taxpayers' money, just a fortnight after the palace spin doctors were trying to tell us the Royals were cutting costs." He added: "If William is training as a RAF pilot then he should abide by all the same rules that apply to other trainees. If he feels he is a security risk and doesn't wish to live on base, he should pay for his own security." However, a spokesman for Clarence House said: "William has lived off-base for two years now and he has lived in this particular cottage since about March. It isn't new."