US tightens financial squeeze on Iran, warns banks over oil money flows

After the US military blockade targeting vessels entering and leaving Iranian ports, the Trump administration on Tuesday stepped up pressure with a financial offensive aimed at the banks and front-company networks that keep Iranian oil revenue moving.

In a post on X late Tuesday, the Treasury Department said it was “moving aggressively with Economic Fury, maintaining maximum pressure on Iran.”

The department warned that foreign financial institutions should be on notice, saying it is prepared to use “the full range of available tools and authorities” and is “prepared to deploy secondary sanctions against foreign financial institutions that continue to support Iran’s activities.”

This also puts greater pressure on jurisdictions that have quietly functioned as financial corridors for Iran’s sanctions-evasion networks.

Banks in the Persian Gulf, Hong Kong and China now face a stark choice: continue facilitating Iran-linked flows and risk losing access to the dollar system or cut those ties before Treasury acts.

That marks a significant escalation.

The maritime blockade was designed to squeeze Iran’s physical oil exports.

This new move targets the financial arteries behind them.

The money trail behind the shadow fleet

According to a Treasury letter shared with Al-Monitor, Washington has evidence that banks in the UAE, Oman, Hong Kong and China allowed Iranian funds linked to illicit activities to move through their systems.

This appears to be the first step toward imposing secondary sanctions, a measure that could cut those institutions off from the US financial system.

That would sharply raise the cost of doing business with Iran far beyond the tankers themselves.

The Treasury letter states that Iran processed at least $9 billion through US correspondent accounts in 2024 using front companies, especially in Hong Kong and the UAE and warned that similar activity continued after 2024.

For Tehran, this is potentially as serious as the naval pressure in Hormuz.

Even if cargoes still find ways to leave Iranian waters through spoofed AIS signals, ship-to-ship transfers or shadow fleet workarounds, the proceeds still need to land somewhere.

That is the vulnerability Washington now appears to be targeting.

The waiver clock is now ticking

Treasury also confirmed that the short-term authorization allowing the sale of Iranian oil already stranded at sea is set to expire in the coming days and “will not be renewed.”

Reuters separately reported the waiver will expire on April 19, tightening pressure on cargoes that had been temporarily allowed to move.

That creates a second countdown alongside the naval blockade.

The first clock is storage. The second is finance.

Cargoes that remain offshore may soon face not only delivery risk, but payment risk as well.

That could hit the shadow fleet where it hurts most: not whether it can move the oil, but whether anyone can safely pay for it.

This also puts greater pressure on jurisdictions that have quietly functioned as financial corridors for Iran’s sanctions-evasion networks.

Banks in the Persian Gulf, Hong Kong and China now face a stark choice: continue facilitating Iran-linked flows and risk losing access to the dollar system or cut those ties before Treasury acts.

In a post on X late Tuesday, the Treasury Department said it was “moving aggressively with Economic Fury, maintaining maximum pressure on Iran.”

This also puts greater pressure on jurisdictions that have quietly functioned as financial corridors for Iran’s sanctions-evasion networks.

Banks in the Persian Gulf, Hong Kong and China now face a stark choice: continue facilitating Iran-linked flows and risk losing access to the dollar system or cut those ties before Treasury acts.

That marks a significant escalation.

The maritime blockade was designed to squeeze Iran’s physical oil exports.

This new move targets the financial arteries behind them.

The money trail behind the shadow fleet

This appears to be the first step toward imposing secondary sanctions, a measure that could cut those institutions off from the US financial system.

That would sharply raise the cost of doing business with Iran far beyond the tankers themselves.

For Tehran, this is potentially as serious as the naval pressure in Hormuz.

Even if cargoes still find ways to leave Iranian waters through spoofed AIS signals, ship-to-ship transfers or shadow fleet workarounds, the proceeds still need to land somewhere.

That is the vulnerability Washington now appears to be targeting.

The waiver clock is now ticking

Treasury also confirmed that the short-term authorization allowing the sale of Iranian oil already stranded at sea is set to expire in the coming days and “will not be renewed.”

Reuters separately reported the waiver will expire on April 19, tightening pressure on cargoes that had been temporarily allowed to move.

That creates a second countdown alongside the naval blockade.

The first clock is storage. The second is finance.

Cargoes that remain offshore may soon face not only delivery risk, but payment risk as well.

That could hit the shadow fleet where it hurts most: not whether it can move the oil, but whether anyone can safely pay for it.

This also puts greater pressure on jurisdictions that have quietly functioned as financial corridors for Iran’s sanctions-evasion networks.

Banks in the Persian Gulf, Hong Kong and China now face a stark choice: continue facilitating Iran-linked flows and risk losing access to the dollar system or cut those ties before Treasury acts.