If Iran and world powers fail to salvage the landmark nuclear agreement, the Biden administration warned Thursday that it will continue to use its sanctions authorities to crack down on Iran’s petroleum exports. 

The Treasury Department’s Office of Foreign Assets Control unveiled sanctions on a network of Iranian petrochemical producers as well as front companies in China and the United Arab Emirates that support a pair of previously blacklisted companies described as “instrumental in brokering the sale of Iranian petrochemicals abroad."

The latest sanctions come as talks to revive the nuclear deal, which would ease sanctions on Iran’s oil sector, remain at a standstill. The Vienna-based negotiations on the Joint Comprehensive Plan of Action derailed in March, at least in part due to Tehran’s demand that Washington remove the Islamic Revolutionary Guards Corps from the US list of foreign terrorist organizations. 

President Joe Biden campaigned on restoring the 2015 deal that his predecessor abandoned, which offered Iran sanctions relief in exchange for curbs on its nuclear program. Biden's special envoy for Iran, Robert Malley, told lawmakers last month that prospects for a deal were “tenuous at best.”