London may be quite a pricey city — but not for some.

A mysterious American tech billionaire may have purchased one of the United Kingdom’s most expensive homes for almost half its original $314 million asking price, according to the Times of London. The still-stratospheric sum: $172.83 million.

The seller is the family of a Saudi prince, former defense minister Khalid bin Sultan al-Saud, who bought the property for around $42 million in the late 1980s before losing it to creditors. This transaction, despite the deep discount, marks the second-most expensive residential deal ever recorded in UK history, according to the Times.

Also known as London’s “White House,” the 40-bedroom palace inside Regent’s Park sits on a lake over 4 acres in the heart of the city — featuring its own underground pool, ballroom and tennis court.  

Other sources, however, said the buyer could be a young Hong Kong-based crypto billionaire. 

Either way, Americans have usurped Russian oligarchs, Middle Eastern petrol princes and Chinese moguls to become “the No. 1 buyers dominating the London real estate market,” said Rory McMullen, who heads Savills’ private office.

“London has captured the interest of Americans looking for a blend of Old World charm and modern luxury — think ‘Downton Abbey’ meets Wall Street,” said Corcoran CEO Pam Liebman, Savills’ stateside partner. “The resilient housing market is a smart move for anyone who wants to diversify their portfolio.” 

A strong US currency and the fact that home prices are down 10% from last fall also helps fuel Americans’ British buying spree.

“We have had a lot of traction in prime properties in London,” said Jenny Lenz, managing director of Dolly Lenz Real Estate. “The clients finally feel we can secure them good deals. They love London as a cultural European home base and Americans are very welcome, so they can do business.”

The mansion’s sale comes as Larry Ellison — co-founder of software giant Oracle, who wants to buy TikTok with the Trump administration — bought a trophy London office building in December from Joseph Lau, a fugitive Hong Kong-based tycoon convicted of bribery and money laundering in Macau, according to reports. 

The 207-year-old Georgian mansion is also known as the Holme — which means “river island” in Saxon — and it was once dubbed “a definition of Western civilization in a single view” by British architectural critic Ian Nairn. 

At 29,000 square feet, the residence also features a formal dining room, elevators, fireplaces, eight garages, a gym — and millions of dollars’ worth of gold leaf. It was bought via Zedra, a Luxembourg-based wealth management company that operates trusts for the wealthy, according to reports. 

The listing attracted its fair share of bidders.

“It’s an awesome house but it needs significant renovation,” a broker familiar with the deal told Gimme Shelter.