US Treasury Secretary Scott Bessent has urged Washington's allies to decide whether they will support a new American campaign to "squash" Iran's economy, warning that the message to partners is essentially "you are either with us or against us". This follows a Truth Social post from President Trump threatening "tremendous economic consequences" for any country offering the Iranian regime a "lifeline", signalling a sharp escalation in economic pressure just months after a US-Iran agreement had promised sanctions relief.

Bessent told CNBC the measures would form part of "the greatest coordinated economic isolation in the history of the world" and warned that anyone continuing to trade with or transfer money to Iran would face the full force of US Treasury enforcement. Further details are due at a press conference on 24 August. The move comes despite a June memorandum of understanding in which the US had pledged to lift sanctions, and follows a period in which Iran's economy has already been battered by protests over soaring living costs, with basic goods prices up 60% and food prices doubling in the year to February 2026; the US previously joined Israel in strikes on Iran and imposed a port blockade and "Operation Economic Fury" sanctions after military action failed to topple the regime.