Fesco was formerly controlled by Ziyavudin Magomedov, who was convicted last year on organised crime and embezzlement charges and is serving a 19-year jail sentence following one of the highest-profile prosecutions of a Russian tycoon in years.

Magamedov says the charges are unfounded and is appealing his conviction. He has previously alleged that the Russian state wanted to bring Fesco - which operates ports, including a key port in Vladivostok - under Rosatom's control.

In January this year, at the request of the Russian Prosecutor's Office, a court transferred to the state 92.4% of Fesco's shares which had belonged to Magomedov and his partners, Russian media reported.

Magomedov filed a lawsuit at London's High Court on July 20 seeking nearly $14 billion over the seizure of his holdings.

The defendants in the case include Rosatom, oil pipeline operator Transneft, private equity firm TPG and UAE-based port operator DP World.

Magomedov, 55, claims his 2018 arrest on the embezzlement charges had prompted what he says is a Russian state-supported expropriation scheme, largely for the benefit of Rosatom and Transneft, according to court filings.

(Reporting by Gleb Stolyarov; Writing by Gareth Jones, editing by Emelia Sithole-Matarise)