Britain's most expensive home goes on sale for £250m with stunning views of St James's Park (oh, and the Queen will be your neighbour)

It's been touted as the largest private home in central London, and the new owner of the property on Carlton House Terrace will count the Queen among their neighbours (wonder if they'll be popping round for a cup of sugar?) and have St James's Park as their back garden.

They will also have bought the most expensive home ever to go on sale in the UK.

The impressive Grade I listed Regency property is discreetly on the market for a record-breaking £250 million - that's 700 times the average price of a London home.

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The current record is held by an apartment in the prestigious One Hyde Park development in London's Knightsbridge, which sold for an astonishing £136 million.

According to an Evening Standard source, the 50,000 sq ft Carlton House Terrace property has been owned by an elderly member of a Middle Eastern royal family since the 1970s, although it has rarely been occupied.

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The owner is thought to have spent millions of pounds lavishly restoring the property over the years, although the Standard source describes the building as being 'very much as it was in its heyday'.

The source added, 'It would be for the new owner to put in the modern toys such as a swimming pool.'

Built to a John Nash design in the 1830s, the cavernous stuccoed mansion, described in the 'confidential' brochure as 'probably the finest residence in London', is over six floors and still boasts many of its original features including a splendid double staircase and a ballroom.

It was once one of London's most influential political salons, but during the First World War it was commandeered as the Enquiry Department for Wounded and Missing, from where scores of British families discovered the fate of loved ones serving in the forces.

The only photographs of the property in the brochure date from the 1890s 'for security reasons', and if this doesn't whet your appetite, well, the owner is apparently happy to wait for the right buyer to come along.

Luckily for him, sales of multimillion-pound properties in London are on the up despite the economic gloom. In the last year alone there were 5,115 sales of homes over £1 million - 12% more than in 2007 before the crash.

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