The meltdown came after US President Donald Trump on Friday announced sanctions against Russian oligarchs close to Vladimir Putin following the diplomatic crisis sparked by the poisoning of former spy Sergei Skripal.
'The Russian government operates for the disproportionate benefit of oligarchs and government elites, ' said Treasury secretary Steven Mnuchin.
The Russian stock market also fell heavily.
Aluminum stocks rose as giant Russian producer United Company Rusal warned on Monday that Trump administration sanctions could land the company in technical default of debt obligations.
The sanctions freeze any assets that those targeted have in U.S. jurisdictions and bar Americans from doing business with them.
The US said it imposed the latest sanctions because of Russian activity in Ukraine, its support of President Bashar al-Assad in Syria's civil war and for subverting Western democracies.
Rusal produced 3.7 million tonnes of aluminium previous year, which according to brokers Argonaut is about 7 percent of the world total. Privately held companies owned or controlled by Deripaska were also sanctioned.
The sanctions could also threaten a tentative revival in Russia's economy, which had only just started to recover from those imposed in response to its annexation of Crimea in 2014.
Russia's prime minister, Dmitry Medvedev, told his government to draw up possible retaliatory steps. "The situation is pretty egregious from the point of view of legality, it tramples on all kinds of norms, and so a thorough analysis is necessary", he said.
EN+, which only listed in London in November having raised $1 billion from City investors despite fears over the potential of further sanctions being imposed on Russian Federation, said it would focus on maintaining its operations and ensuring it "abides by all applicable laws and regulations".
"The company's initial assessment is that it is highly likely that the impact may be materially adverse to the business and prospects of the group", the company said.