The metals tycoon and former Arsenal co-owner is also reported to be targeted in a package of sanctions being prepared by the US Treasury Department.
It comes a day after Everton Football Club cut commercial ties with Mr Usmanov, who had close links with its majority shareholder Farhad Moshiri.
The club said it was ending all commercial agreements with the tycoon’s USM Holdings, as well as telecoms firm Megafon and smartphone maker Yota.
Mr Usmanov bought Dilbar in 2016 for a reported $600m from German shipbuilder Luerssen, which custom-built it for him over a year.
The luxurious vessel, which weighs 15,917 tonnes, is usually manned by a crew of 96 people and boasts the largest swimming pool ever installed on a yacht.
It also has two helicopter pads, a sauna, a beauty salon and a gym and can host up to 24 people in 12 suites.
The yacht is part of Mr Usmanov’s vast fortune, which is estimated at $19.7bn by Bloomberg.

The Amore Vero is owned by a company linked to Rosneft chief executive Igor Sechin