London's new luxury hotel: US embassy in London to become five-star hotel

"We have studied the building's design and its history as well as its surroundings to deliver an architecturally and socially coherent proposal, which will transform this purpose-built embassy into a world-class hotel," says Mr Chipperfield.

"A new chapter in our special relationship begins in early 2017 with our move to a new US Embassy in Nine Elms. Grosvenor Square will write a new chapter of its own, one that I hope retains an imprint of America's deep and abiding history here," said Mr Barzan.

Other current London projects managed by Qatari Diar include the Southbank Place riverside complex as well as the joint development of the East Village on the former Olympic site and the Elephant and Castle town centre.

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11 incredible hotel conversions around the world

Royal Horseguards, UK

The five-star Royal Horseguards hotel, just a stone's throw from London's Trafalgar Square, occupies eight floors of Whitehall Court, an imposing Grade I-listed building with a fascinating history. Built in 1884 in the style of a French chateau, it housed the original Scotland Yard, hosted secret service meetings during the two world wars, and – more recently – emergency talks between the Treasury and bankers tasked with tackling the credit crunch. Other former residents include George Bernard Shaw and H.G. Wells, while the northern end – which adjoins the hotel – has been the National Liberal Club's HQ since Gladstone's time (it's members only, but you can pop your head round the door and admire the marble staircase).

Malmaison Oxford, UK​

Oxford Prison closed in 1996 before being redeveloped into a shopping and heritage complex - and a luxury hotel. The Malmaison uses converted jail cells as guest rooms, although those parts of the prison associated with corporal or capital punishment are now offices. It is, bizarrely, a popular wedding venue.

No Man's Fort, UK

No Man's Fort, located in the middle of the Solent, is just 1.4 miles from the Isle of Wight, and a mile from Portsmouth. After an extensive renovation, the man-made island is now a luxury hotel. Built between 1867 and 1880 at the request of Prime Minister Lord Palmerston, the fort was built in order to protect Portsmouth from an attack by Napoleon III (an attack that never came). The four-storey fort has 22 guest bedrooms - appropriately nautical in style - which have original iron ceilings and windows made from the former gun ports.

Four Seasons Istanbul, Turkey

Despite being converted into a luxury hotel, the Four Seasons Sultanahmet still given hints to the building's former use. The old exercise yard has been converted into a courtyard for outdoor dining, while watchtowers are now elevator shafts. Engravings can also be seen detailing the names and professions of former prisoners.

The Liberty Hotel, US

In its previous guise as Boston's Charles Street Jail, this building was home to some of Boston's most notorious criminals. Conditions were so revolting that in 1972 the US Government declared it in violation of the inmates' constitutional rights. Some 30 years later it was transformed into a slick hotel.

Castel Monastero, Italy​

Set in Chiantishire's rolling hills in Siena, Castel Monastero has had various incarnations. First, it was an 11th-century monastery, then a castle, followed by a country residence for nobility and finally, a hamlet. Now it's a hotel. There's a hydrotherapy spa which was designed by the people responsible for the spa at the well-known Forte Village in Sardinia, and includes seawater pools, a Hammam and Finnish sauna. Gordon Ramsay also has a restaurant on site.

Hotel Monasterio, Peru

Cusco's Hotel Monasterio, originally built in 1592, is a great entry point to Machu Picchu. The hotel, part of the Belmond group, works with the Belmond Hiram Bingham train which goes up to Sacred Valley and includes a guided tour and afternoon tea at the Sanctuary Lodge. After the exploration, you can visit the spa, get a 'bath butler' to fill up your marble tub, or ask for oxygen to be pumped into your room, which will help the effects of Cusco's high altitude.

Quinta Real Zacatecas, Mexico

The luxury hotel was built around the restored 19th century San Pedro bullfighting ring, which ceased to host the traditional spectacle in 1975. The hotel's restaurant now looks over the old arena, while the brick-walled bar is located where the bullpens used to be.

Ramathra Fort, India

Built in the 17th century, the historic fort in Rajasthan stands high on a hill in rare wilderness. Ravi and Gitanjali Rajpal, descendants of its original Rajput builder, have restored part of the vast complex to create six stylish suites. There are also six luxury tents set out on a lawn below. On the ramparts there are sun loungers with glorious views over lakes and forests full of bird life and the hotel's walled vegetable garden. There is also a whirlpool tub in a turret.

Ulvesund Fyr lighthouse, Norway​

Built in 1870, the lighthouse at Cape Trafalgar guides ships through one of the most treacherous – and beautiful – passes in the Nordfjord, on the west coast of Norway. As well as the beacon itself (a small tower built in 1985 when the lighthouse was automated) there are three cottages, sleeping 16 between them, within a wildflower-filled garden with a swing, a hammock and two goats.

Admiralty Arch, UK

Plans to turn London's Admiralty Arch into a luxury hotel, also just yards from Trafalgar Square, were announced in 2013, but little has been heard about the possible development since.

The Telegraph, London

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