US Treasury Prepares Broader Secondary Sanctions in Economic Pressure Campaign Against Iran

The US Treasury Department is expected on Monday to broaden the scope of secondary sanctions it can impose on entities and countries that maintain business ties with Iran.

Treasury Secretary Scott Bessent will hold a press conference to detail the measures, which President Donald Trump and Bessent have described as an economic D-Day. The goal is to sever remaining financial lifelines and force an end to the nearly six-month conflict that has restricted the Strait of Hormuz and Gulf energy exports.

A source familiar with the plans said the action aims to give a final warning to countries to cut business ties with Iran. Bessent intends to make clear that countries must side with the United States or risk having key companies cut off from the dollar-based financial system.

In an opinion piece published in the Financial Times, Bessent wrote that at dawn begins the single greatest financial offensive ever marshalled against an adversary. The administration has mapped Iran's oil-smuggling and sanctions-evasion network and will present that information to countries helping Iran as a warning.

Iran has responded with its own threats. Mohsen Rezaei, leader of Iran's Supreme National Security Council, warned that support for US economic sanctions by other nations will be seen as an act of war. He said Iran would target alternative oil shipping routes to the Strait of Hormuz if necessary.

Iranian officials stated that if the economic war continues, not a single drop of oil will be exported through the Strait of Hormuz or from anywhere in the Persian Gulf. Iran has also announced the discovery of more than 7.5 trillion cubic feet of new natural gas reserves in Fars province.

The military phase of the conflict has seen a pause in direct strikes between the United States and Iran for weeks, but no meaningful talks have resumed to end the fighting. The new sanctions package is intended to shift pressure from kinetic action to economic isolation.

China, India and Turkey maintain significant commercial links with Iran. How the secondary sanctions will apply to them remains a central question. The Iranian rial has already fallen to new lows against the dollar ahead of the announcement.

Bessent is expected to stress that any remaining financial channels, including banks and third-country facilitation, must be closed. The measures build on decades of existing sanctions and the wartime disruption of Iranian energy infrastructure.

Whether the economic campaign produces the desired change in Iranian policy or further escalates the confrontation over Gulf shipping will become clearer after the details are released and regional responses take shape.