This move will significantly impact the operations of Rusal, which has warned of a possible default.
Rusal produced 3.7 million tonnes of aluminium previous year, which according to brokers Argonaut is about 7 percent of the world total. Shares in Rusal and EN+ had already fallen sharply on Friday in response to the sanctions, which were announced towards the end of trading in London.
Billions of pounds were wiped off the value of Russian companies yesterday as the business empire of one of its most prominent oligarchs teetered on the brink in the face of USA sanctions.
Under the sanctions, Americans are generally prohibited from doing business with the companies, and people of other nationalities could face sanctions themselves if they facilitate transactions for the firms.
The sanctions were weighing on broader markets in Russian Federation. The state-controlled bank is seen as a barometer for the wider Russian economy. Shares in Russian steelmaker Evraz were the biggest fallers on the FTSE 100 in London, closing 14.4% lower.
The sanctions also hit Norilsk Nickel, whose shares were down 16 percent. As Bloomberg points out, the move also raises questions for Glencore and its billionaire chief Ivan Glasenberg, the commodity giant who is one of Rusal's top shareholders, owning an 8.75 percent stake and also the biggest buyer of its metal, having bought $2.4 billion of metal from it past year. Privately held companies owned or controlled by Deripaska were also sanctioned. He features in Robert Mueller's investigation into Russian meddling in the USA election because of his ties to Paul Manafort, Donald Trump's former campaign chairman. "This is an outrageous business from the point of view of illegality, from the point of view of flouting all the norms, and of course careful analysis is needed here", said spokesman Dmitry Peskov.
En+ Group and Rusal both released statements on Monday that said "it is highly likely" that the sanctions would "be materially adverse" to their businesses.
"The US list may not be the final list and it feels like there will be more sanctions, so investors do not know which, if any, stocks to hold", said John Meyer, mining analyst at SP Angel.