The Trump administration has moved to dramatically expand its economic pressure campaign against Iran, warning foreign governments and companies that continued trade with Tehran could expose them to the same punishing sanctions applied to the Islamic Republic itself. The escalation marks one of the most aggressive uses of secondary sanctions in recent memory, drawing sharp reactions from Beijing, New Delhi, and several European capitals. As our earlier coverage of Iran sanctions expansion detailed, the administration’s strategy is designed to leave third-party nations with an unambiguous choice: do business with Iran or do business with the United States.
The policy thrust was outlined across multiple official statements in late August 2026. Al Jazeera reported in its article Trump threatens Iran’s partners: How do secondary sanctions work? that the White House is invoking broad executive authority to penalise foreign financial institutions, energy firms, and shipping companies that facilitate Iranian oil exports or broader commerce. Analysts estimate Iran’s oil exports currently run at approximately 1.4 million barrels per day, with China absorbing roughly 90 percent of that volume — making Beijing the most exposed third-party actor and the most consequential target of the secondary sanctions threat.
The Mechanics of Secondary Sanctions
Primary sanctions prohibit US persons and entities from engaging in transactions with a designated country or individual. Secondary sanctions go considerably further. They give Washington the authority to penalise foreign actors — companies, banks, or even sovereign governments — that have no US nexus but nonetheless conduct business with the sanctioned party. In effect, they allow the United States to export its domestic restrictions to the rest of the world, leveraging the centrality of the US dollar and access to American markets as coercive tools.
According to DW reporting on the package, the administration has explicitly warned that countries failing to comply will “share in the isolation” currently applied to Iran. That language is deliberate. It signals that the United States is prepared to restrict dollar-clearing access and correspondent banking relationships for non-compliant foreign financial institutions — a threat that carries genuine systemic weight given that roughly 88 percent of global foreign exchange transactions involve the US dollar. Cutting off a mid-sized bank from dollar clearing can effectively freeze its ability to participate in international trade finance, regardless of where it is headquartered.
The legal architecture rests primarily on executive orders issued under the International Emergency Economic Powers Act, which grants the president sweeping authority to regulate international commerce during declared national emergencies. Iran has been subject to a continuous national emergency declaration since 1979, giving successive administrations broad statutory cover for escalatory measures. The new tranche of designations targets tanker operators, insurance underwriters, and port facility operators in third countries that service Iranian cargo.
Which Economies Face the Greatest Exposure
The countries most acutely exposed to secondary sanctions risk are those with deep commercial ties to Iran that simultaneously rely on access to US financial infrastructure. China tops that list by a considerable margin. As Iran sanctions coverage noted, Chinese state-linked refineries and trading firms have quietly absorbed the bulk of Iranian crude since Washington reimposed maximum pressure policies. Several smaller Chinese banks already operate under existing US sanctions designations, but a broadening of secondary measures to larger institutions would represent a qualitative escalation.
India presents a more complex case. New Delhi imported significant volumes of discounted Iranian crude before the previous sanctions regime tightened, and Indian refiners have shown interest in resuming those flows. Indian officials have historically resisted pressure to align fully with US sanctions policy, citing energy security and sovereign commercial interests. However, with Indian banks and technology firms heavily integrated into dollar-denominated trade and US capital markets, the secondary sanctions lever carries real leverage over New Delhi as well.
According to Business Standard, Iran has vowed retaliation and indicated it may accelerate efforts to route trade through alternative settlement mechanisms and currencies, including bilateral currency swap arrangements with China and Russia. Tehran has also threatened to restrict access to the Strait of Hormuz, through which approximately 20 percent of global oil supply transits daily — a move that would send crude prices sharply higher and complicate the geopolitical calculus for Washington’s Gulf allies. Whether such threats translate into action remains uncertain, but the rhetoric underscores how significantly the stakes have risen on all sides of this expanding economic confrontation.