British billionaire slashes the price of his London mansion by $13 million, saying the rich are fleeing the UK. See inside the storied property.

• British billionaire David Sullivan has cut the price of his London mansion by about $13 million.
• The businessman, who owns the West Ham United soccer club, said he is taking a loss on the property.

British billionaire David Sullivan has cut the price of his London mansion to £65 million (about $85 million), knocking about $13 million off of the previous asking price.

Sullivan, an owner of the east London-based soccer club West Ham United, told Bloomberg that while he would now be selling the property for a loss, "you have to be realistic."

"Interest rates are high — they're coming down but not much," Sullivan said.

"I also think what the government is doing to the non-doms isn't very nice, and a lot of rich people are leaving the country as a result of what they anticipate in the budget. Three or four of my friends already have gone to Monaco or Dubai," he added.

Sullivan, 75, was referring to planned changes to government policy that would remove certain tax advantages for wealthy UK residents whose permanent home — for tax reasons — is outside the UK.

The proposed changes have led to uncertainty in the market, according to real-estate firm Knight Frank, with London's "super-prime market" seeing 22% fewer transactions in the 12 months to July compared to the year prior.

And that's not ideal for Sullivan, who told Bloomberg he spent about £75 million (about $98 million) on his Marylebone property — £27 million (about $35 million) to buy the house in 2015 and almost £50 million (roughly $65 million) refurbishing it.

According to Knight Frank, the 21,000-square-foot house at 33 Portland Place was built in 1775. It features 10 bedrooms, 10 bathrooms, a swimming pool, a wine cellar, a cinema room, a sauna, and a "sky lounge."

One of the property's former owners, Edward Davenport, was convicted of a multimillion-pound fraud in 2011. He was released in 2014 after he was granted clemency on the grounds of ill health, the Guardian reported.

Under Davenport's ownership, the house hosted several famous guests and was famed for holding raucous parties.

Supermodel Kate Moss once shot a campaign for Agent Provocateur on the property, while British music icon Amy Winehouse used it as the set for her "Rehab" music video. It was also used to film scenes for the Oscar-winning film "The King's Speech."

Davenport's website shows photos of him posing with various celebrities, from Paris Hilton to Daniel Radcliffe. One photo also shows him with Sullivan.

Davenport purchased the house from the Sierra Leone High Commission in 1999.

Who is David Sullivan?

Sullivan is worth about £1.2 billion (roughly $1.6 billion), according to The Sunday Times Rich List.

The 75-year-old first made his money in the adult entertainment industry before moving into media, owning the Daily Sport and Sunday Sport newspapers.

Speaking to The Times of London about his career in 2006, Sullivan said: "I always had a burning desire to be fabulously rich because I came from a fabulously poor background."

"I am not embarrassed by what I have done," he added. "I am not one of those people who tells the neighbours I'm in the print business. I'm in the adult entertainment industry and I have met some lovely girls and made a lot of money. I have given an awful lot of people a lot of pleasure and I have never hurt anyone."