(Bloomberg) -- Family members of sanctioned Russian billionaire Oleg Deripaska are seeking to sell their stake in En+ Group International PJSC, according to people familiar with the matter.

Deripaska’s ex-wife Polina Yumasheva and former father-in-law Valentin Yumashev are looking for buyers of their stakes, as well as holdings owned by Deripaska’s children, said the people, who asked not to be identified because the discussions are private.

They said discussions have been preliminary and informal to sound out potential acquirers, and there’s no work being done on a deal. No one has expressed interest in purchasing the stakes and it’s possible a buyer won’t be found, the people said.

Yumashev declined to comment. Polina didn’t respond to questions sent to her Facebook account or representatives of Forward Media Group, a publishing house that she owns. An En+ spokeswoman declined to comment.

In an interview with Russian media outlet RBC, Polina said she hasn’t held any negotiations yet on selling the stake.

En+ owns a majority stake in United Co. Rusal, one of the world’s biggest aluminum producers, and runs hydropower plants in Russia. Finding a buyer could face hurdles given the chief owner is still Deripaska, who remains under U.S. sanctions.

En+ was sanctioned last year by the Treasury’s Office of Foreign Assets Control in response to Russia’s “worldwide malign activities,” which included annexing Ukraine’s Crimean peninsula.

Treasury officials agreed to lift the penalties on Deripaska’s companies in January as part of an agreement that he would step back from running the businesses. The billionaire still owns about 45% of En+ shares. Under the agreement with OFAC, he’s allowed to vote 35% of the shares and the rest are done by independent trustees.

Polina and her father own 6.75% of the company. Her two teenage children have 3.42%. The voting of their shares is also via trustees.

En+ global depositary receipts are listed in London and Moscow, but infrequently traded so a market valuation is difficult to determine. Based on the London share price, the company is worth $5.3 billion.

The Financial Times reported last month that VTB Group, which is also a large En+ shareholder, held talks with Chinese companies over a potential investment. The newspaper cited people familiar with the matter saying VTB had been approached by two Chinese state-related industrial groups about a share sale.

(Adds comment from Polina Yumasheva in fifth paragraph.)

To contact the reporters on this story: Yuliya Fedorinova in Moscow at yfedorinova@bloomberg.net;Irina Reznik in Moscow at ireznik@bloomberg.net;Andrey Biryukov in Moscow at abiryukov5@bloomberg.net

To contact the editor responsible for this story: Lynn Thomasson at lthomasson@bloomberg.net

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