Downing Street has denied allegations that the prime minister 'wasted' a reported �40,000 of public money on a Royal flight to take his family on holiday.

The Blairs flew to Italy on a BAe146 aircraft used by the Royal Squadron.

"We find it extraordinary that while senior Royals have pulled in their horns to save public money, Mr Blair can take his family around Europe in this extravagant manner," a Buckingham Palace aide was quoted as saying in The Mail on Sunday.

The Queen regularly flies on the BAe 146 but other Royals such as the Prince of Wales have hired smaller commercial aircraft and helicopters to save money.

But a No 10 spokeswoman said holiday flight arrangements for the Blairs had not changed from those in place for previous prime ministers.

The two aircraft in the Royal Squadron - the HS125 and the BAe146 - have been used to fly both Margaret Thatcher and John Major on holiday.

Cook in charge

The spokeswoman added the flight had to be taken for security reasons.

She said the family would pay the commercial equivalent for Mrs Blair and the couple's four children.

However, shadow defence spokesman Iain Duncan Smith said Mr Blair's behaviour was "outrageous" and said he viewed his wife and children as "the real royal family".

The Blairs are in Italy for the start of a three-week summer holiday.

Foreign Secretary Robin Cook is the most senior cabinet minister still in London because Deputy Prime Minister John Prescott is away in Cyprus and Chancellor Gordon Brown is on honeymoon.

Mr Prescott, who is expected back in Britain early next week, has in previous years taken over in the prime minister's absence.

However, Downing Street was keen to stress that Mr Blair was still in charge and that the "wonders of modern technology" would keep him firmly in touch with any issues in Britain.

The Blairs are to split their time between Italy and France and return by the end of the month.

Soon after they arrive, the prime minister will pose next week for pictures for the press with his wife, Cherie, and their children, Euan, 16, Nicky, 14, Kathryn, 13, and baby Leo.

The Blair family initially ruled out the traditional holiday photocall after some papers published pictures of Leo at his christening in defiance of a request for privacy.

They relented following discussions with the Press Complaints Commission.

The Conservative Party leader, William Hague, has gone to Malaga in southern Spain, with his wife, Ffion. The Liberal Democrat leader, Charles Kennedy, will be touring in the south of France.