Washington is escalating its financial war on Tehran, with US Treasury Secretary Scott Bessent announcing the start of what he calls an “economic D-Day” against the Islamic Republic. In a post on X and an opinion piece in the Financial Times on Sunday, Bessent described the campaign as “the single greatest financial offensive ever marshalled against an adversary.”
Bessent claimed that President Donald Trump's military actions had “significantly dismantled Iran’s military capabilities and weakened its nuclear programme.” He said the administration is now “entering the endgame,” with economic measures beginning “at dawn.” The stated goal: to “sever every economic lifeline that sustains the tyrannical regime until Tehran stands alone.”
The Treasury chief warned countries and entities that continue to buy or transport Iranian petroleum, facilitate financial flows through exchange houses and free trade zones, handle flights, maintain ship registries, or enable seaborne fuel transfers that any remaining links would “accelerate their own isolation.” This follows Trump's own declaration on Truth Social last week of “the most crushing economic operation ever taken against any country.”
Despite the dramatic rhetoric, specific measures have yet to be unveiled. According to Bessent's outline, the package could centre on secondary sanctions against nations and firms that keep purchasing Iranian oil, process its finances, operate related banks, or support shipping and other commercial channels—layered on top of the existing naval blockade. Bessent is scheduled to hold a press conference at 7 PM CET on Monday to announce the concrete steps.
Market reaction and European stakes
Oil prices were lower on Monday morning even as the rhetoric intensified. Brent crude, the international benchmark, traded at around $91.5 a barrel, roughly 2% below Friday's close, while West Texas Intermediate stood at about $86.2, down 1.5%. The dip may reflect profit-taking after recent gains and reports of a temporary rise in tanker movements through the Strait of Hormuz. According to shipping data cited by Axios, around 40 tankers transited the southern channel on Friday night, moving roughly 16 million barrels—higher than the 15-20 vessels recorded on preceding nights. Overall volumes through the waterway remain well below pre-conflict levels.
For Europe, the stakes are considerable. The continent remains heavily dependent on energy imports, and any disruption to Gulf supply routes could reignite inflation and strain already fragile economies. European capitals, particularly in Berlin, Paris, and Rome, will be watching closely to see whether the US measures force them to choose between transatlantic solidarity and their own commercial interests. The Iranian president's recent call for an end to the war from a position of strength suggests Tehran is also calculating its options.
The US move also raises broader questions about the use of economic statecraft. Critics argue that secondary sanctions, which target third-country entities, could undermine the rules-based international order. The ICC president has warned that such measures could erode the international rule of law, a concern echoed by European diplomats who have long favoured multilateral engagement over unilateral pressure.
Meanwhile, the EU has backed the ICC in the face of US sanctions on court officials, signalling a potential rift in transatlantic unity. European leaders may also be wary of the precedent set by Washington's aggressive use of the dollar and financial system as weapons, a tactic that could eventually be turned against European companies or even allies.
As the world awaits the detailed sanctions package, the immediate focus is on the Strait of Hormuz, through which about a fifth of global oil passes. Any further tightening of the naval blockade could send prices soaring, hitting European consumers and businesses hard. The coming days will reveal whether the US can sustain its “maximum pressure” campaign without alienating its European partners or triggering a broader conflict.
