THE US assets of a Russian oligarch with alleged mob ties have been frozen including his mansion where feds found Roman Abramovich’s ex-wife and his kids.

Oleg Deripaska, 50, who is close with Vladimir Putin and President Trump’s ex campaign manager Paul Manafort, has been placed on a sanctions list over his alleged mafia connections - claims he disputes.

Washington has frozen the Aluminium billionaire's US-based assets, including his massive mansion at 11 East 64th Street in Manhattan, reports The New York Post.

However, Deripaska has arranged to have the children and ex-wife of his business partner Abramovich to live in the sprawling New York property, The Post has learned.

The Chelsea owner, 51, recently transferred £71million worth of property to his ex-wife, Dasha Zhukova, 37, a magazine editor who listed her current address as 11 East 64th St., according to property records.

Abramovich is reportedly dating Deripaska’s estranged 38-year-old wife Polina

Roman’s ex Zhukova, who the footy boss has two kids with, is dating Greek shipping heir Stavros Niarchos.

There is no suggestion that she is in a relationship with Mr Deripaska.

The five-story £33m townhouse was previously owned by the late art dealer Alec Wildenstein and his then-wife Jocelyn Wildenstein – who has been dubbed “catwoman” due her fascination with plastic surgery.

It is also eight doors down from another of Mr Wildenstein’s former properties, 19 East 64th Street, which was sold for £61m last year - making it the most expensive townhouse in the city.

One of Zhukova’s good friends is senior adviser to the US President Ivanka Trump.

The two are so close that Zhukova and Abramovich often travelled and socialised with Trump and her husband, presidential son-in-law and adviser Jared Kushner.

Deripaska bought the East Side property for £33m in 2008, property records show.

FBI agents unsuccessfully tried to flip Deripaska in exchange for information on Russian organised crime and the Kremlin’s support for President Trump’s 2016 campaign, the New York Times reported last month.

Deripaska had previously worked on a “thwarted effort” to rescue an FBI agent who had been captured in Iran, the Times reported.

Before the 2008 global economic crash, the oligarch was the ninth richest person on the planet and the wealthiest man in Russia.

The feds are also negotiating with him to give up some of his European-based operations to keep them running free of sanctions, Treasury officials say.

According to the officials in Washington, when the government freezes assets anyone who does business with a sanctioned person and sanctioned companies could be subject to sanctions themselves.

Representatives for Deripaska and Zhukova did not respond to requests for comment.

Roman Abramovich, who is also known to have close ties to Russian President Putin, married Zhukova in 2008.

The pair announced that they had separated in August 2017.