An huge mansion that was designed by Buckingham Palace's architect and overlooks Regent's Park has been put on the market for £185million.

The John Nash-designed property, 1-18 York Terrace East, would become the second most expensive house sale in the UK if bought for the asking price.

The property firm selling the mansion, built between 1821 and 1826, says a person with 'billions' who wants a house in the UK should inquire, with the company's chief executive expecting interest from Asia, particularly from wealthy Chinese individuals.

Current owner, property investment firm, Zenprop UK, is thought to have paid £200million for the mansion four years ago - though its chief executive claims it was actually purchased for less than the current listing price.

Derrick Beare, from Zenprop UK, said the sale 'is not for me to make a return, it's pretty much to get my money back and move on'.

He added: 'The current price is a result of Brexit and the pandemic. It should be more, but I don't think I can get more in this market. It won't appeal to many people but we only need one person. The kind of person with billions, who wants a place in London.'

The building was completed in 1826 by regency architect Nash who also designed Buckingham Palace, Regent Street and Brighton's Royal Pavilion.

It was originally built as 18 separate homes, designed by Nash for the Crown Estate's Regency Park development, before being combined into one for government offices after World War II. It was used as luxury accomodation for international students until 2016.

Pictured: A computer-generated image of how the inside of the mansion could look, complete with a lavish staircase and a reception area that looks like it belongs in a hotel lobby. The mansion was originally built as 18 separate houses when completed in 1826

In 1967, the terrace was converted to student accommodation by the International Students Trust. Until 2016, it was used by students as accommodation, before being sold to the current property developer owners

A student reads a book in the lobby of the then-International Students House at York Terrace East, Regent's Park, before it was bought by a property developing firm

A prospective buyer had last year considered a bid of more than £200 million for the mansion but had pulled out because of the Brexit negotiations. Pictured is a computer-generated image of a sitting room in the building, with its Regent's Park-facing windows promising natural light and beautiful views

The property firm selling the mansion, built between 1821 and 1826, says a person with 'billions' who wants a house in the UK should inquire. Pictured is a CGI image of the stunning exterior, with bright lights and a stunning architecture sure to catch the eye

The current owners of the stunning property are hoping to sell it to one wealthy individual who will be able to design it as above, complete with a floor to ceiling shoe rack, gorgeous lighting and luxurious bed

The computer-generated images showcase the potential of the space, with the expectation that the property can be thoroughly developed, though it might add even more millions to the price tag. With the property overlooking Regent's Park, stunning views are another attraction

A stylish bathroom, an imagining of how the interior of the John-Nash designed property could look after it is bought by its new owner

York Terrace East is a huge space and has been described as being a unique opportunity for a buyer to redesign in their image, with some of the breathtaking possibilities highlighted by Savills, included this opulent dining area, complete with an impressive fireplace and even a bar

After the First World War, the fashion for larger homes began to change and there was some modification to the building's footprint.

During the Second World War, the building suffered bomb damage and was very nearly demolished.

In 1947, following public outcry and a Royal Commission, the decision was made to preserve the building and most of it was requisitioned as government offices and occupied by the Ministry of Works.

In 1967, the terrace was converted to student accommodation by the International Students Trust, but many of the original internal features were lost after a fire in 1969.

The buildings were listed as Grade 1 in 1970.

Current owners, Zenprop UK, who are associated with Zenprop Property Holdings, one of South Africa’s premier property development and investment companies, acquired the building from International Student House in 2016.

They then agreed a long leasehold extension with the Crown and took the property through planning with Westminster City Council to restore it to residential use over a period of three years.

As part of the planning obligations, the owners are developing 44 affordable housing units in the borough for St Martin in the Fields Almshouse Charity at the site known as Chesterfield Lodge in St John's Wood.

Believed to be the first time an entire Nash terrace has come to the open market, 1-18 York Terrace East in London's Regent's Park, has a guide price of £185 million.

The Grade 1 Listed 117,000 sq ft building has planning permission for the development of two houses and 26 apartments with 42 underground parking spaces.

Pictured: What an interior room could look like, complete with luxury sofas and a floor to ceiling shoe rack. The building was completed in 1826 by regency architect Nash who also designed Buckingham Palace, Regent Street and Brighton's Royal Pavilion

Pictured: A computer-generated living room, complete with gorgeous floor to ceiling windows giving stunning views of Regent's Park. Around £80-90 million needs to be spent transforming the interior, with even more needed if the buyer wants to transform it into flats

Pictured: One of the ways rooms within the property can be designed, in a classic design sure to be a hit with guests and family alike, complete with a piano and comfy seats

Pictured: A proposed living room, complete with a fire place that looks perfect for a winter or autumn evening . If the mansion was bought by an individual it would represent the second most expensive house ever sold in the UK

The closeness to Regent's Park allows for stunning dinner views, with this mocked up photo showcasing how a dining room could be designed, which is sure to impress guests

The property could be the second most expensive in British history if it meets its asking price, with the mansion sure to attract interest despite its hefty price tag. This CGI bedroom shows the luxury available with the property, the opulence and style of the mansion a highlight

The stunning mansion, which has 117,000 square feet of floor space, previously served as government offices and then student accommodation after it was damaged during the Blitz

The terrace was part of John Nash's masterplan for Regent's Park. It was built by James Burton between 1821 – 1826 and was originally configured as 18 single family houses

Planning officials rejected an application to turn the Grade 1-listed building in to 13 townhouses because they would be too big.

Instead, the developers have planning permission to create 26 flats and two houses, though the property firm wants to sell to individuals.

Mr Beare told the Financial Times that he estimates £80-90 million needs to be spent transforming the interior, with even more needed if the buyer wants to transform it into flats.

The roof, floors and non-original stairs would need to be removed and replaced. The gardens facing the park would also have to be dug up as part of the excavation of extra basement space.

However, Mr Beare insists that there remains interest in the property from very wealthy individuals.

He said a prospective buyer had last year considered a bid of more than £200 million but pulled out because of the Brexit negotiations.

The buyer had planned to turn the building in to several very large homes for himself, his sons and their staff.

Stephen Lindsay, head of Savills St John's Wood, commented: 'Nothing on this scale in such a prime London location has ever come up for sale. It is an opportunity to create a special and extensive private estate within the tranquil surrounds of Regent's Park, moments away from Marylebone High Street and the West End.'

He added: 'Working on this historic terrace to reinstate its prime residential use, in accordance with the original architectural vision for the park and with the support of the Crown as freeholder, has been a very rewarding experience.

'It is a unique property which is now fully assembled and we look forward to seeing its magnificent restoration.'

If it was bought by an individual it would represent the second most expensive house ever sold in the UK.

In January, Chinese property tycoon Cheung Chung-kiu bought a 45-room mansion overlooking Hyde Park for more than £200million.

London properties are a big-hit with foreign buyers, with the wealthy flocking to the UK's capital from all over the globe.

American billionaire Ken Griffin bought 3 Carlton Gardens for £95million in 2019, despite the home being on the market for £125million two years before that.

US buyers spent an average of £7.3 million ($9.2 million) when buying in such prime locations, up from an average of £5million over the past ten years.

The proportion of London homes sold to Americans in the city's most desirable districts nearly doubled in 2019, when compared to 2018.

Meanwhile, wealthy families from the Middle East are also rapidly buying up London's luxury homes in the wake of the area's instability.

In recent years, Middle Eastern governments and sovereign funds have ploughed their vast resources into the capital, buying development sites and high-value buildings, according to research by a Mayfair property firm.

They spent £4.4billion from 2006 to 2014, which gave them control of nine of central London's largest development sites, equating to 28,000 new homes.

The super-rich bought prime residential properties in Knightsbridge, Mayfair, Kensington, Belgravia and Regent's Park - so much so that half of all buyers of Mayfair property worth more than £10million are from the Gulf.

The computer-generated images of bedrooms reflect the luxuriousness of the property, with buyers sure to fall in love with the warm, cozy vibe. London properties are a big-hit with foreign buyers, with wealthy individuals from Asia expected to bid for York Terrace East

An entire room dedicated to designer shoes and handbags. Mr Beare said a prospective buyer had last year considered a bid of more than £200 million but pulled out because of the Brexit negotiations

Stephen Lindsay, head of Savills St John's Wood, added: 'Working on this historic terrace to reinstate its prime residential use, in accordance with the original architectural vision for the park and with the support of the Crown as freeholder, has been a very rewarding experience'

Mr Lindsay added: 'It is a unique property which is now fully assembled and we look forward to seeing its magnificent restoration.' Pictured is how a bedroom could look

The potential to design the space is endless, with the mansion originally made up of 18 houses. If bought, it would be the second most expensive house in the UK

The roof, floors and non-original stairs would need to be removed and replaced. The gardens facing the park would also have to be dug up as part of the excavation of extra basement space

John Nash, the architect behind Buckingham Palace and Regent's Park

John Nash, remembered for his work on Buckingham Palace, Regent's Park and Regent Street in London, is one of the most famous architects of the 18th and early 19th centuries.

He was born in January 1752 and after an early education received training from the architect Sir Robert Taylor.

After early education, Nash was trained by the architect Sir Robert Taylor and worked as a surveyor and builder in the city of London.

In 1777 Nash established his own business and later inherited £1,000 from an uncle which he decided to risk on the building of houses in Great Russell Street and Bloomsbury Square.

The buildings failed to rent out and Nash was declared bankrupt in 1783.

Returning to London in 1797, Nash then designed a number of Gothic castles around the country, in places such as Luscombe Castle in Devon and Caerahays Castle in Cornwall.

Nash soon came under the patronage of the Prince Regent, later King George IV.

In 1806 he was appointed Surveyor General of Woods, Forests and Parks and from 1810 onwards worked solely for the prince. By 1813 he had been appointed official architect to the Office of Works, which meant advising parliamentary commissions on things such as new church buildings.

This was when he designed Regent's Park, Buckingham Palace and two theatres in Haymarket.

When George IV died in 1830, Nash lost his royal protector amid a backlash about the extravagance of the King's reign. Buckingham Palace had cost thousands, millions in today's terms, and Nash ultimately retired. He died a few years later in May 1835.