The U.S. will unveil "the single greatest financial offensive ever" against Iran on Monday, Treasury Secretary Scott Bessent said, while Tehran threatened to seize vessels that violate transit rules in the Strait of Hormuz.
The looming escalation comes as both sides missed a 60-day ceasefire window to reach a deal, closing off the formal truce mechanism aimed at ending the Middle East war now in its sixth month.
In a post on X on Sunday evening stateside, Bessent said "at dawn begins an economic D-Day," framing the coming measures as the "endgame" for Washington's campaign against Tehran.
The new measures will add to an extensive sanctions regime already targeting Iran's banking, energy, aviation and cryptocurrency sectors. The Iranian rial hit a new open-market low on Sunday, with the dollar surpassing 2 million rials.
Bessent also warned that "any nation that serves as a financial artery of a withering regime should expect to share in its isolation." Tehran has responded by warning Gulf neighbors against joining U.S. economic measures.
Oman's foreign minister is scheduled to visit Tehran on Tuesday for bilateral talks.
