Trump threatens new sanctions on Iranian oil buyers, escalating tensions with China

President Donald Trump on Thursday issued a stark warning to global purchasers of Iranian oil, threatening sweeping secondary sanctions in a move that appears to directly challenge China, Tehran’s top oil customer. The announcement, made via his Truth Social platform, adds fuel to the already tense U.S.-China trade relationship and marks a sharp escalation in Trump’s ongoing “maximum pressure” campaign against Iran.

“All purchases of Iranian Oil, or Petrochemical products, must stop, NOW!” Trump wrote. “Any Country or person who buys ANY AMOUNT of OIL or PETROCHEMICALS from Iran will be subject to, immediately, Secondary Sanctions. They will not be allowed to do business with the United States of America in any way, shape, or form.”

The warning comes just weeks after the U.S. sanctioned several Chinese companies accused of circumventing restrictions to buy Iranian oil. According to tracking data from energy analytics firm Vortexa, nearly 90% of Iran’s oil exports are destined for China, which reportedly hit a new record in March with 1.8 million barrels per day imported from Iran.

Though Chinese government data on these transactions is often opaque, analysts say Beijing employs a network of intermediaries and "shadow fleet" shipping methods to evade U.S. sanctions and the Western financial system. These backdoor transactions have become a vital lifeline for Iran’s sanctioned economy, enabling Tehran to fund regional proxies and nuclear development efforts.

State Department spokeswoman Tammy Bruce said Thursday the new sanctions are consistent with Trump’s longstanding objective of completely halting Iran’s oil trade. “The Iranian regime uses the revenue it generates from these sales to finance attacks on U.S. allies, support terrorism around the world, and pursue other destabilizing actions,” she said.

This latest pressure comes amid broader trade hostilities between the U.S. and China. In April, Trump raised tariffs on Chinese goods to a cumulative 145% in retaliation for China’s refusal to curb fentanyl exports and its alleged trade abuses. The tariff escalation has drawn criticism from American business leaders and economists, who warn it could further strain global supply chains and consumer prices.

In parallel, U.S.-Iran nuclear negotiations—already a fragile endeavor—have also been thrown into uncertainty. A fourth round of indirect talks, which was tentatively set for this weekend in Rome, has been postponed. Oman, the key mediator in the discussions, cited “logistical reasons” for the delay.

“For logistical reasons we are rescheduling the U.S.-Iran meeting provisionally planned for Saturday May 3rd. New dates will be announced when mutually agreed,” Omani Foreign Minister Badr Albusaidi posted on X.

The U.S. State Department downplayed the postponement, stating the Rome meeting was “never confirmed,” but reiterated that Washington remains open to future rounds of dialogue.

Trump has tasked Middle East envoy Steve Witkoff, a longtime ally and real estate developer, to lead the Iran talks. Witkoff’s appointment reflects the Trump administration’s pivot to informal diplomatic channels, but critics argue the lack of a traditional foreign policy team may hinder serious negotiations.

As the president pushes for a full halt to Iranian oil exports and ramps up trade conflict with Beijing, the geopolitical and economic stakes continue to rise. Trump appears poised to double down on aggressive foreign policy tactics that defined his first term.