The United States is preparing to launch what Treasury Secretary Scott Bessent has described as the “single greatest financial offensive ever marshalled against an adversary”, signaling a dramatic expansion of Washington’s economic campaign against Iran.US Treasury Secretary Scott Bessent will hold a press conference at 1 p.m. EDT (1700 GMT) on Monday, amid threats to unveil tougher measures against a country that has suffered near-constant economic sanctions since the 1979 Islamic Revolution.Unlike previous rounds of sanctions primarily aimed at Tehran, the new measures appear designed to target the countries, companies and financial networks that continue to facilitate Iranian trade, particularly oil exports, reflecting a growing US focus on Iran’s external economic lifelines rather than the regime alone.In an opinion piece published in the Financial Times on Monday ahead of the announcement, Bessent argued that nations which purchase Iranian petroleum, facilitate financial transactions, host Iranian commercial activity or otherwise help Tehran evade sanctions risk sharing in its economic isolation. The language points to increased pressure on jurisdictions that maintain commercial ties with Iran.Looking at Iran’s largest trading partners and strategic allies gives some indication as to what countries are likely to feel the sharp edge of US economic pressure.