The U.S. Treasury will lift sanctions on Windalco's parent company UC Rusal and its parent En+.
The move will water down the toughest penalties imposed since Moscow's 2014 annexation of Crimea.
In April, the U.S. Treasury imposed sanctions on Oleg Deripaska the owner of Rusal, En+ and other companies in which he owns stakes, citing malign activities by Russia, prompting turmoil in global aluminium markets including Jamaica.
After lobbying by European governments, Washington postponed enforcement of the sanctions and started talks with Deripaska's team on removing Rusal and En+ from the blacklist if he ceded control of Rusal.
The U.S. Treasury says Deripaska will remain under sanctions.
But, the three companies - Rusal, En+ and power firm EuroSibEnergo - have agreed to restructure to reduce his stakes.