The United States on Thursday imposed sanctions on Hong Kong and Emirati companies and a network of Iranian firms that help export Iran’s petrochemicals, a step that may aim to raise pressure on Tehran to revive the 2015 Iran nuclear deal.

The US Treasury department said it had imposed penalties on two companies based in Hong Kong, three in Iran, and four in the United Arab Emirates, as well as on Chinese citizen Jinfeng Gao and Indian national Mohammed Shaheed Ruknooddin Bhore.

“The United States is pursuing the path of meaningful diplomacy to achieve a mutual return to compliance with the Joint Comprehensive Plan of Action,” Under Secretary of the Treasury for Terrorism and Financial Intelligence Brian Nelson said in a statement, referring to the 2015 nuclear agreement.