Why has the US hit an India-based company with Iran-related sanctions?

The United States Department of the Treasury has included a petrochemicals trading firm based in Mumbai among an "international network" of eight companies allegedly "involved in the sale of hundreds of millions of dollars' worth of Iranian petrochemicals and petroleum products to end users in South and East Asia". This is possibly the first instance of US sanctions against Iran targeting an India-based company in recent years. The Department of the Treasury's action comes days after External Affairs Minister S Jaishankar visited the US for talks with senior Biden Administration officials including Secretary of State Antony Blinken and National Security…