The US slapped sanctions on Thursday on firms accused of involvement in Iran’s petrochemical and petroleum trade, including those located in China and India, putting pressure on Tehran as it works to resurrect the 2015 Iran nuclear agreement.

U.S. In a statement, Secretary of State Antony Blinken announced that Washington had identified two Chinese entities, Zhonggu Storage and Transportation Co Ltd and WS Shipping Co Ltd, as part of efforts to foil sanctions evasion on the export of Iranian petroleum and petrochemical goods.

Blinken accused Zhonggu Storage and Transportation Co Ltd of operating a commercial crude oil storage facility for Iranian petroleum and WS Shipping Co Ltd of being a ship manager for a vessel that has transported Iranian petroleum products.

Reuters could not immediately reach the two companies for comment.

The U.S. Treasury Department also slapped sanctions on a network of companies involved in what it said was the sale of hundreds of millions of dollars’ worth of Iranian petrochemical and petroleum products to South and East Asia.

The action targeted Iranian brokers and front companies in the United Arab Emirates, Hong Kong and India, the Treasury said in a separate statement.

The Iranian mission to the United Nations in New York did not immediately respond to a request for comment.

Washington has increasingly targeted Chinese companies over the export of Iran’s petrochemicals as the prospects of reviving the nuclear pact have dimmed. Indirect talks on the accord, formally known as the Joint Comprehensive Plan of Action (JCPOA), have broken down.

The 2015 agreement limited Iran’s uranium enrichment activity to make it harder for Tehran to develop nuclear arms, in return for lifting international sanctions.

But then-U.S. President Donald Trump ditched the deal in 2018, saying it did not do enough to curb Iran’s nuclear activities, ballistic missile program and regional influence, and reimposed sanctions that have crippled Iran’s economy.

Washington warned that it would continue to accelerate enforcement of sanctions on Iran’s petroleum and petrochemical sales so long as Tehran continues to accelerate its nuclear program.