The move not only sent the Russian stock index to an all-time high but also relieved the toughest penalties imposed since 2014 Crimean Crisis, following a 10-month-long lobbying campaign in the U.S.
En+ GDRs rose by 9.47 percent shortly after the start of trading and Rusal shares added 6.24 percent, although both gave up some of their gains later.
Aluminum prices on the London Metal Exchange (LME) dropped as much as 1.4 percent after the open.
On Jan. 28, the LME said it had lifted its suspension on storing Rusal-produced metal in LME-approved warehouses with immediate effect. In a statement, LME also wrote its members can freely enter into contracts with the aluminum giant and its affiliates.
Earlier this month, 11 of Trump's fellow Republicans joined the Democrats in the USA senate in an effort to keep the sanctions on Russian firms including En+ Group, Rusal, and even JSC EuroSibEnergo.
Congressional Democrats are zeroing in on Secretary Steven Mnuchin following the Treasury Department's controversial decision to ease sanctions on companies linked to a Russian oligarch with ties to the Kremlin, with some raising questions about his personal business dealings and potential for conflicts of interest.
The leaders of four House of Representatives committees said they were considering legislation to ensure Russian aluminium giant Rusal and its parent En+ comply with the agreement that allowed them to be removed from a US sanctions list.
"This action ensures that the majority of directors on the En+ and Rusal boards will be independent directors ... who have no business, professional or family ties to Deripaska", Treasury said.
Putin's ally himself remains subject to the U.S. sanctions, Reuters reported, while the companies had agreed to unprecedented transparency for the Treasury into their operations. Among them were several enterprises belonging to Oleg Deripaska, including Rusal, Basic Element, En+, Russian Machines, EuroSibEnergo, GAZ Group, B-Finance investment company and Agroholding Kuban.
The oligarch and his business empire were included on a U.S. treasury department sanctions blacklist after the Trump administration said that he and fellow tycoons were profiting from association with a Kremlin conducting "malign activities" around the globe.
By barring nearly any commercial relationship with one of the world's largest producers of a metal key to worldwide supply chains, US policymakers ensured this time the economic pain would be felt not only in Russian Federation.
The United States is a major consumer of aluminum.
For European consumers, premiums at $69 a tonne, down almost 60 percent since early May, are expected to slide due to high stocks of aluminum held by traders in the region.