Trump declares ‘economic warfare’ on Iran, warns countries aiding Tehran

United States President Donald Trump has pledged “economic warfare” against Iran and threatened any country that trades with it.

The war between the United States and Iran, started by the U.S. and Israel in February, appears stalemated, with peace talks stalled, Tehran keeping the key Strait of Hormuz shut, and Washington persisting with a naval counter-blockade of Iran.

Under pressure at home over the economic impacts of the war and with midterm elections looming, Trump appeared to be searching for alternative ways to pressure Tehran.

In a post on his Truth Social on Thursday, August 20, 2026, the president announced “the MOST CRUSHING ECONOMIC OPERATION EVER TAKEN AGAINST ANY COUNTRY! This will be Economic Warfare and Isolation on an unprecedented scale.”

“ANY country that allows its financial institutions, businesses, airports, or government entities to provide any type of lifeline to Iran will itself face TREMENDOUS Economic Consequences,” Trump added.

Iran’s Foreign Minister Abbas Araghchi on Thursday dismissed the plan as a continuation of “failed policies”, which he said would bring Washington “further defeat”.

Araghchi wrote on X: “The so-called ‘Economic D-Day’ is a diversion from America’s own crisis: unprecedented debt & surging interest costs. Doubling down on failed policies will only bring further defeat – and enmity of Iranians.

“US economic terrorism threatens global economy and sovereignty worldwide.”

Despite the heavy international sanctions, Iran found ways to continue exporting its oil, with China the biggest buyer.

In his threat to those helping Iran, Trump did not mention any country by name, nor did he say what punishment third countries might face.

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In August 2025, the United States imposed an additional 25 per cent tariff on India for buying Russian oil.

Trump also listed several activities that he said needed to stop immediately, including “oil smuggling, swap lines, cash transfers, exchange houses, ship registries, front companies.”

Like Russia, Iran operates a so-called shadow fleet of tankers, all of which are under international sanctions, to continue its oil trade.

It’s unclear what additional impact any fresh sanctions would have, given the United States blockade of Iranian ports, AFP reported.

Tehran, though, continues to exert its own economic pressure campaign by keeping the Strait of Hormuz largely closed. Before the war, around a fifth of global oil supplies travelled through the strait.

Attacks on shipping in Hormuz have continued, despite the lull in the wider war, while on Wednesday Iran’s Revolutionary Guards warned Gulf countries against assisting the United States.

The war has also continued to spread, sucking in and reigniting Yemen’s smouldering civil war. On Thursday, the Revolutionary Guards warned that Saudi Arabia would not be able to contain Tehran’s allies, the Houthi rebels.

The group, which controls swathes of Yemen and has been at war with Riyadh for over a decade, has declared a maritime blockade of Saudi Arabia and attacked ships in the Red Sea.