In its latest investigation, the Foundation claims the $US700 million Scheherazade is crewed by Russia's Federal Protective Service, which is tasked with guarding the President Vladimir Putin.
The 140-metre German-built yacht is registered in the Cayman Islands and owned by Bielor Asset, which is a trust company in Majuro.
Italian police have failed to ascertain whether the two-year-old yacht belongs to a Russian individual subject to the European Union's sanctions regime.
