US threatens unprecedented financial blockade on Iran, warns backers

US Treasury Secretary Scott Besant announced on Sunday that the United States will launch the "largest financial blockade ever" against Iran, warning of severe consequences for countries providing financial support to Tehran.

In an opinion piece published by the Financial Times, Besant stated that any country serving as a financial lifeline for Iran or facilitating the flow of funds to it "will share in its isolation and must consider the consequences," stressing that "any country supporting Tehran will be regarded by Washington as globally ostracized."

The US official emphasized that countries continuing to support the Iranian regime are "exceeding the limits of US tolerance," questioning whether Tehran’s allies are willing to risk their relationships for its sake. He added that the financial isolation Washington intends to impose on Iran "will make military force unnecessary."

Besant noted that President Donald Trump has devastated Iran’s economy in unprecedented ways, explaining that the US goal is "to sever every economic lifeline" to Iran. He also warned that Trump would respond "swiftly and firmly" if Iran attacks US forces or its neighbors in the Gulf.

Reactions and mutual warnings

Besant had earlier threatened to impose "the toughest sanctions in history" on Iran, while Iranian Foreign Minister Abbas Araghchi rejected the US threats, describing them as "a sign of desperation," and insisted that the expected US measures would not succeed in defeating Tehran.

In the same context, the US president warned of economic consequences for any country providing "any form of vital support to Iran."

Sanctions fallout and crisis developments

These escalations come as Iran’s economy faces significant pressure from recent international and US sanctions, with the country’s infrastructure suffering repeated strikes since the United States and Israel launched attacks on February 28.

Nevertheless, Tehran continues to adopt a defiant stance nearly six months into the conflict, as the crisis has led to an almost complete halt in shipping through the Strait of Hormuz, following Iran’s refusal to allow unauthorized oil tankers to pass through this vital global energy corridor.