Shares in Aughinish Alumina parent Rusal fell almost 3pc in Hong Kong in Monday trading. The drop came as more US politicians sought to re-evaluate a plan to lift sanctions on the business.
The sanctions have raised fears over the future of Limerick-based Aughinish. US Democratic Senator Chuck Schumer, minority leader in the Senate, said he would force a vote next week on a measure to block the US Treasury Department's plans to lift sanctions on Rusal.
The sanctions were imposed because of the company's links to oligarch Oleg Deripaska, an ally of US President Vladimir Putin. Mr Putin has been accused of meddling in the 2016 US presidential election.
Yesterday a number of influential Democrats in the House of Representatives demanded a meeting with Treasury Secretary Steve Mnuchin on the issue.
Additional reporting Bloomberg