Bessent warns Iran of 'toughest sanctions in history', urges China to 'get with the programme'

US Treasury Secretary Scott Bessent has warned that Washington is preparing what he described as the “toughest sanctions in history” against Iran, as the Trump administration intensifies its effort to economically isolate Tehran and presses China and other countries to cooperate. Bessent said the United States intends to combine its existing blockade with sweeping economic restrictions in an attempt to cripple Iran’s finances. The Treasury Secretary is expected to provide details of the new measures at a press conference on Monday.

The announcement signals an escalation of Washington’s economic campaign against Tehran amid continuing tensions over the Strait of Hormuz and months of conflict that have disrupted energy supplies and unsettled global markets.

Washington plans economic squeeze

Speaking to CNBC, Bessent described the strategy as a “one-two punch”, combining the blockade with an unprecedented sanctions regime. He argued that economic pressure could prove more effective than an expansion of military operations and said Washington intended to place severe strain on the Iranian government.

The Treasury Secretary also suggested that tougher sanctions could reduce the likelihood of the conflict developing into a broader conventional war. His comments came after US President Donald Trump warned countries against providing economic or other assistance to Tehran as Washington seeks to cut Iran off from international trade.

The details of the sanctions have yet to be formally announced, but the administration’s comments indicate that countries, companies and financial institutions maintaining significant commercial links with Iran could come under increased scrutiny.

China emerges as key target

China is likely to be central to Washington’s strategy because it is by far the most important destination for Iranian oil. Bessent said more than 80 per cent of Iran’s exported crude currently goes to China, making Beijing crucial to any attempt to sharply reduce Tehran’s oil revenues.

Calling on Beijing to cooperate, Bessent said China should “get with the programme”. He pointed to China’s dependence on energy supplies from the Gulf and argued that Beijing also had an interest in stability and the uninterrupted movement of oil through the region.

Asked whether Washington could impose penalties on China if it continued buying Iranian oil, Bessent stopped short of publicly outlining specific measures. He indicated that discussions with Beijing over the issue would be better handled privately.

Pressure follows failed ceasefires

The tougher economic approach comes after two ceasefire arrangements announced by the United States and Iran, in April and June, failed to produce a lasting settlement. Both efforts had sought to restore the free movement of shipping through the Strait of Hormuz and create a pathway towards ending the conflict.

The strait remains critical to the global energy market, having carried roughly one-fifth of internationally traded oil before the conflict intensified. Disruption to shipping through the waterway has contributed to volatility in crude prices and heightened concerns about global energy supplies.

Iran has rejected Washington’s sanctions strategy and described US economic restrictions as a form of “economic terrorism”. Tehran has faced extensive American sanctions for decades and has developed networks for continuing oil exports despite restrictions.

Trump widens warning to Iran’s partners

The latest threat also broadens the confrontation beyond Iran itself by placing countries doing business with Tehran under pressure. Trump has warned that nations providing support to Iran could face economic consequences, raising the prospect of secondary sanctions aimed at foreign buyers, banks, shipping companies and other intermediaries.

For Washington, the effectiveness of the new campaign may ultimately depend on how successfully it can restrict Iran’s oil revenues without triggering a wider confrontation with major trading powers, particularly China.

Bessent, however, expressed confidence that intensified economic pressure combined with restrictions on Iranian trade would weaken Tehran significantly, with the administration preparing to disclose the next stage of its campaign on Monday.