It boasts a hot-tub, Beduin-style tented lounge, sumptuous master bedroom and finely stocked games room — and will whisk you around the world in a few hours.

With a price of £225 million, the flying palace, converted from the world’s biggest passenger aircraft, appears to be the latest accessory for the multibillionaire who has no qualms about his carbon footprint.

An anonymous Middle Eastern head of state will soon be taking delivery of the luxuriously appointed Airbus A380, which costs about £5,000 an hour to fly and will accommodate a retinue.

The order, Airbus’s first from a private buyer, has boosted the fortunes of the aircraft, which completed its maiden flight from Europe to the United States last week after years of production delays.

Edése Doret, a New York-based aircraft interior designer, told The Times: “I am contractually obliged not to reveal the identity of my client. He wants to remain anonymous, as do most of my clients, usually for security or political reasons.”

Mr Doret, 39, has spent two years perfecting the interior of the double-decker aircraft. One of its most personalised features is the Beduin-tent-style “oasis lounge” with vast curtains hanging from the ceiling, low tables and pillows on the floor. On the walls is a fibre- optic desert scene mosaic.

Mr Doret said: “The rest of the plane is quite minimal and stylish. It looks like a New York loft with lots of wooden floors, wood veneers, leather in various colours and nickel. Olive green and light beige are the predominant colours. There are definitely no gold taps.”

To comply with Federal Aviation Administration regulations, the Airbus’s hot-tub — believed to be only the second fitted in an aircraft — will have a rapid drainage system that can empty in seconds to a tank in the cargo hold.

There are 42 in and 70 in wall-mounted flat-screen televisions throughout, with live television, video on demand and internet. The lower cargo area has crew accommodation and a hold big enough for a large Mercedes. A missile-defence system is also a possibility.

The A380, which can seat up to 853 passengers, is not only the largest aircraft in aviation history but also the most expensive. In a deal still to be finalised, it will cost £150 million to buy and £75 million to upgrade. The work will take another two years. A typical private jet, the Gulfstream G550, which carries 10 to 15 passengers costs £25 million.

Exact running costs for the A380 are unavailable, but its rival, the Boeing 747-400, costs more than £5,000 an hour to fly. Airbus’s smaller A320 costs about £1,500 an hour, and a Gulfstream G550 costs about £1,150 an hour. Boeing says that it has taken 11 orders for its two biggest models — the 747 and 787 Dreamliner — in the past two years for “VIP use”.

Sergey Brin and Larry Page, the founders of Google, bought a used Boeing 767-200 for £7.5 million in 2005.

The biggest flying mansions can equal or surpass the cost of the world’s biggest yachts, which cost up to £150 million.

Boeing says that most private buyers for new aircraft are from the Middle East, but Americans, Europeans, Russians and Asians are also starting to place orders. After signing purchase contracts and making a 10 per cent deposit, customers typically get their aircraft in a few years.

One aircraft customiser, Lufthansa Technik, a subsidiary of the German airline, has been in talks with “a couple of potential A380 customers” and their interior designers, according to Aage Duenhaupt, a spokesman. The company, with a workforce of 1,100 engineers and outfitters, expanded one of its wide-body hangars in Hamburg last year to prepare.

A Swiss-based customiser, Jet Aviation Management, recently finished an Airbus 320-200, which normally seats about 150, for Saad Group, a Saudi conglomerate. John Leahy, Airbus’s chief commercial officer, said: “You can host an elegant dinner party on the ground in a Third World country. After you bid your guests a fond farewell, you close the door and head home.”

Apart from the expense, there seems to be only one problem to owning a flying palace: they are too big to land at many of the world’s glitziest destinations. Airports such as those at Nice and Aspen have runways too short for the aircraft, or lack the ground equipment to deal with them.

Asked whether an A380 could try to fly into Aspen, Mr Leahy said: “Only once.”

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