The chairman of West Ham United has said the Government’s proposed crackdown on non-doms “isn’t very nice”, as he cut the asking price of his London mansion by £10 million amid a tough prime property market.

David Sullivan, who is a majority shareholder of the football club, revealed he was selling the property at a loss.

The mansion, in London’s Marylebone, is currently up for sale with Knight Frank for £65 million, boasting 10 bedrooms and bathrooms, and features including a swimming pool, spa, cinema room, gym and wine cellar.

But Mr Sullivan said he bought it for £27 million in 2015, and spent nearly £50 million renovating it, which took the total spend to about £75 million.

“I’m selling it at a loss now, but you have to be realistic,” he told Bloomberg.

“Interest rates are high — they’re coming down but not much. 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 have already gone to Monaco or Dubai,” he added.

Labour pledged in its election manifesto to crack down on so-called non-doms, meaning UK residents whose permanent home, or domicile, is outside of the UK for tax purposes.

Non-doms currently only have to pay tax on the money they earn in the UK.

The upcoming Budget statement could see the policy changed after Labour said it would remove “the outdated non-dom tax regime”, but reports have suggested that it could risk driving ultra-rich residents out of the country.

The Treasury said last week that it was “committed to addressing fairness in the tax system”, and that it would be replacing the system with a “new internationally competitive residence-based regime”.

Mr Sullivan bought a controlling stake in West Ham with fellow businessman David Gold in 2010.

He built a successful career with Mr Gold in the adult magazine publication business.