For years, Chinese independent refineries quietly purchased massive quantities of sanctioned Iranian crude oil at steep discounts, creating a billion-dollar trade pipeline that Washington largely failed to stop. That pipeline is now broken. A combination of aggressive U.S. Treasury sanctions, a 25% tariff on Iran’s trading partners signed by President Trump, and the dramatic escalation of military conflict in the region following the killing of Iranian Supreme Leader Khamenei on February 28, 2026, has driven Iranian crude discharges at Chinese ports down from roughly 1.4 million barrels per day in 2025 to approximately 1.13 million bpd in early 2026. At least five refineries in China’s Shandong province have stopped buying Iranian crude entirely, fearing they will be next on the sanctions list.
The disruption did not happen overnight. It is the result of a sustained maximum pressure campaign that finally found its teeth when the U.S. Treasury designated Shandong Shengxing Chemical Co., a Chinese “teapot” refinery, for purchasing more than $1 billion worth of Iranian crude — the first time Washington had ever directly sanctioned one of these smaller Chinese refineries. That single action sent shockwaves through an industry that had operated with relative impunity for years. Now, with open military conflict disrupting shipping through the Strait of Hormuz and Iranian tankers idling offshore, the question is no longer whether the supply will be disrupted but how long the disruption will last and who bears the economic cost. This article examines how the sanctions campaign escalated, how the war has compounded the supply crisis, what it means for China’s energy-dependent manufacturing sector, how Russia is positioning itself to fill the gap, and why the geopolitical fallout may be far from over.
Table of Contents
- How Were Chinese Companies Buying Sanctioned Iranian Oil for So Long?
- What Changed With the Shandong Shengxing Sanctions?
- How the Killing of Khamenei Upended the Oil Market
- Who Wins and Who Loses From the Supply Disruption?
- The Payment Networks That Made It All Possible
- What China’s Energy Security Looks Like Now
- Where Does This Go From Here?
- Conclusion
- Frequently Asked Questions
How Were Chinese Companies Buying Sanctioned Iranian Oil for So Long?
The short answer is that they exploited every gap in the enforcement system. iran maintained a “shadow fleet” of tankers that turned off tracking transponders, conducted ship-to-ship transfers at sea, and falsified cargo documentation to disguise the origin of crude oil shipments. On the Chinese side, the primary buyers were so-called teapot refineries — smaller, independent operations concentrated in Shandong province that lack the international banking relationships and reputational concerns of state-owned giants like Sinopec or PetroChina. These teapots bought Iranian crude at discounts of $5 to $10 per barrel below benchmark prices, which gave them a significant cost advantage over competitors using market-priced oil. According to Bloomberg, without access to this cheaper supply, many teapots would struggle to remain profitable, and energy and manufacturing costs across China’s broader economy would rise. The payment mechanisms were equally opaque. Reporting from The Wire China revealed that Chinese buyers routed payments through unregistered financial vehicles, connecting infrastructure financing to oil payments.
In practice, funds would be deposited and then used to pay Chinese contractors working on infrastructure projects inside Iran — a barter-like arrangement that kept transactions off the books of major banks and outside the reach of U.S. sanctions enforcement. This system worked for years because previous administrations, while imposing sanctions on paper, lacked the political will or intelligence resources to target the actual end-buyers in China. The scale was enormous. Iranian crude oil was flowing into China at roughly 1.4 million barrels per day through 2025, representing the vast majority of Iran’s total oil exports. The U.S. Treasury identified 8 vessels and sanctioned 12 entities and 1 individual as part of the shadow fleet network, but those numbers only scratch the surface of an operation that moved millions of barrels across thousands of miles of ocean using dozens of ships and intermediaries.
What Changed With the Shandong Shengxing Sanctions?
The designation of Shandong Shengxing Chemical Co. by OFAC was a genuine turning point. For the first time, the U.S. government went after a Chinese refinery directly, not just the Iranian exporters or the ships carrying the cargo. The Treasury Department documented that Shengxing had purchased more than $1 billion worth of Iranian crude, including oil sourced from a front company for Iran’s Islamic Revolutionary Guard Corps-Qods Force — a designated terrorist organization. That detail mattered because it tied the purchases not just to sanctions evasion but to material support for an entity the U.S. considers a direct national security threat. The deterrent effect was immediate.
Five additional refineries in Shandong province stopped buying Iranian crude after the Shengxing designation, according to OilPrice.com, not because they had been sanctioned themselves but because they feared being next. This is how effective sanctions enforcement is supposed to work — one high-profile action changes the risk calculus for an entire industry. However, this approach has a significant limitation: it only works as long as Chinese companies believe the U.S. will actually follow through with additional designations. If enforcement stalls or the political winds shift, the teapots could resume purchases. The history of Iran sanctions is littered with periods of strict enforcement followed by periods of quiet relaxation, and Chinese refiners have long memories. In late February 2026, OFAC reinforced the message by sanctioning another dozen vessels and associated networks tied to Iran’s shadow fleet that had carried crude to china throughout 2025 and early 2026. The cumulative effect of these actions drove Iranian crude oil loadings from Persian Gulf terminals down to below 1.39 million bpd in January 2026 — a 26% drop from the same period a year earlier, according to RFE/RL. About one-third of Iranian tankers were idling offshore or conducting evasive maneuvers as of early 2026, per tracking data from Kharon.
How the Killing of Khamenei Upended the Oil Market
The sanctions campaign was already producing results when the situation escalated dramatically. On February 28, 2026, U.S. and Israeli airstrikes killed Iranian Supreme Leader Ayatollah Ali Khamenei, triggering a widening regional conflict that transformed a supply disruption into a potential supply crisis. The immediate consequence was chaos in the Strait of Hormuz, through which roughly 20% of the world’s oil passes daily. Iran’s Revolutionary Guards moved to threaten shipping through the strait, driving up insurance premiums, inflating delivery costs, and causing some tankers to reroute entirely. For China, the war created a compounding problem. Even those teapot refineries that had been willing to continue purchasing Iranian crude despite the sanctions risk now faced a practical barrier: getting the oil safely from the Persian Gulf to Chinese ports became significantly more expensive and uncertain.
Asia Times reported that China now confronts a halt to reliable shipping through the Strait of Hormuz, with sharply increased risks for any vessel attempting the passage. The United Against Nuclear Iran (UANI) shipping tracker confirmed as of March 16, 2026, that disruptions to Iranian oil shipments were ongoing amid the conflict. The war also eliminated any remaining ambiguity about where U.S. policy was headed. President Trump had already signed an executive order imposing a 25% tariff on Iran’s trading partners as part of the maximum pressure campaign. With active military operations underway, the political space for Chinese companies to quietly resume Iranian oil purchases effectively vanished. The question shifted from “will the U.S. enforce its sanctions?” to “what replaces 1.4 million barrels per day of cheap crude in the Chinese market?”.
Who Wins and Who Loses From the Supply Disruption?
The most obvious winner, at least in the short term, is Russia. With Iranian supply curtailed and Chinese refiners scrambling for alternatives, Moscow has increased oil exports to fill the gap, benefiting from both higher prices and redirected demand. The Carnegie Endowment for International Peace noted that the disruption has effectively boosted Russian oil revenues at a time when Western governments are still attempting to enforce price caps on Russian crude — an irony not lost on analysts who have pointed out that the maximum pressure campaign on Iran may be inadvertently subsidizing the Kremlin’s war effort in Ukraine. The clearest losers are China’s teapot refineries and the downstream industries that depend on them. These refineries operated on thin margins even with access to discounted Iranian crude.
Without it, they face a choice between buying more expensive oil from Russia, Saudi Arabia, or other suppliers — which squeezes their margins and potentially forces some to shut down — or scaling back production, which ripples through China’s petrochemical, plastics, and manufacturing sectors. Bloomberg reported that energy and manufacturing prices across China’s economy are expected to rise as a result. For American consumers, the picture is mixed. Higher global oil prices could eventually translate into higher gasoline prices at home, though the U.S. is now a net energy exporter and less vulnerable to supply shocks than it was a decade ago. The tradeoff the Trump administration has implicitly accepted is that short-term price pressure is worth the strategic goal of cutting off Iran’s oil revenue, which funds its military and proxy operations across the Middle East.
The Payment Networks That Made It All Possible
One of the most underappreciated aspects of the China-Iran oil trade is the financial plumbing that kept it running. Standard international payment systems like SWIFT are closely monitored by U.S. regulators, which makes direct bank transfers for sanctioned oil purchases extremely risky. Chinese buyers adapted by creating parallel payment channels that avoided the formal banking system entirely. The Wire China documented how Chinese companies routed payments through unregistered financial vehicles that connected infrastructure financing to oil purchases. The mechanism worked like this: Chinese firms would deposit funds into intermediary accounts, and those funds would then be used to pay Chinese contractors working on infrastructure projects inside Iran — roads, power plants, telecommunications networks.
Iran received both the infrastructure and the oil revenue, while the payment trail was obscured from Western regulators. This arrangement had the added benefit of advancing China’s Belt and Road ambitions in Iran while simultaneously funding oil purchases. The warning here is that even as the oil trade is disrupted, these financial networks do not disappear overnight. They can be repurposed for other sanctioned transactions or reactivated if enforcement pressure eases. U.S. policymakers have historically focused on the visible parts of the sanctions evasion chain — ships, ports, refineries — while giving less attention to the financial intermediaries that make it all work. Until those payment channels are dismantled or their operators sanctioned, the infrastructure for resuming large-scale Iranian oil purchases remains intact.
What China’s Energy Security Looks Like Now
China imports roughly 70% of its crude oil, and any disruption to a major supply source creates real vulnerability. The loss of cheap Iranian crude is particularly painful because it cannot be easily replaced barrel-for-barrel at the same price. Saudi Arabia and other Gulf producers sell at market prices, and while Russia offers discounts on its own sanctioned crude, the logistics of significantly scaling up Russian deliveries to China take time — pipeline capacity is fixed, and rerouting tankers requires planning.
The broader concern for Beijing is that this episode exposes a structural weakness in China’s energy strategy. By relying heavily on sanctioned oil from Iran (and to a lesser extent, Venezuela), China saved money in the short term but created a dependency on supply lines that could be disrupted by U.S. policy decisions at any time. The current crisis — where sanctions, tariffs, and military conflict have simultaneously hit the same supply source — represents a worst-case scenario that Chinese energy planners will be studying for years.
Where Does This Go From Here?
CNN analysis has noted that Trump needs China’s cooperation to resolve the broader global oil crisis, but China is unlikely to cooperate — particularly given the tariff threats and the perception in Beijing that Washington is deliberately weaponizing energy markets. The diplomatic channel between the two countries on energy issues is effectively frozen, and neither side appears willing to make concessions. The forward-looking picture depends heavily on how the military conflict in the region evolves.
If the Strait of Hormuz remains contested, the disruption to Iranian oil flows will persist regardless of sanctions enforcement. If the conflict stabilizes, the question becomes whether Chinese refiners — burned by the Shengxing precedent and wary of further U.S. action — will attempt to rebuild their Iranian supply chains. History suggests they will try, but the sanctions architecture is now significantly more robust than it was even a year ago, and the political costs of being caught have never been higher.
Conclusion
The disruption of Chinese purchases of sanctioned Iranian oil represents one of the most consequential shifts in global energy markets in years. It is the product of three forces converging simultaneously: a U.S. sanctions campaign that finally targeted the actual buyers rather than just the sellers, an executive order imposing tariffs on Iran’s trading partners, and a military escalation that physically disrupted the shipping routes these transactions depend on. Iranian crude discharges at Chinese ports have fallen from 1.4 million bpd to roughly 1.13 million bpd, with further declines likely as the conflict continues. The consequences will be felt across multiple economies.
China faces higher energy costs and potential manufacturing slowdowns. Russia benefits from redirected demand but risks overextending its own production capacity. Global oil prices face upward pressure at a time when the world economy can least afford it. And the teapot refineries of Shandong province — the small, scrappy operators that built their business models on cheap sanctioned crude — are facing an existential reckoning. Whether this disruption proves temporary or permanent depends on decisions being made right now in Washington, Beijing, and whatever remains of Tehran’s leadership structure.
Frequently Asked Questions
What are “teapot” refineries in China?
Teapot refineries are smaller, independent oil refineries concentrated primarily in China’s Shandong province. Unlike state-owned giants such as Sinopec, they lack international banking relationships and are less concerned about reputational risk, which made them the primary buyers of discounted sanctioned Iranian crude oil.
How much Iranian oil was China buying before the disruption?
Chinese ports were receiving approximately 1.4 million barrels per day of Iranian crude throughout 2025. That figure dropped to roughly 1.13 million bpd in early 2026 following sanctions enforcement and military escalation, with further declines expected.
Why did the U.S. sanction Shandong Shengxing Chemical Co.?
The U.S. Treasury designated Shandong Shengxing for purchasing more than $1 billion worth of Iranian crude oil, including from a front company tied to Iran’s IRGC-Qods Force. It was the first-ever U.S. sanction against a Chinese teapot refinery and was intended to deter other Chinese refiners from continuing to buy Iranian oil.
How were Chinese companies paying for Iranian oil without getting caught?
Chinese buyers routed payments through unregistered financial vehicles that connected oil payments to infrastructure financing. Funds were deposited into intermediary accounts and used to pay Chinese contractors working on projects inside Iran, effectively creating a barter system that bypassed monitored banking channels.
Is Russia benefiting from the disruption?
Yes. Russia has increased oil exports to China to help fill the gap left by reduced Iranian supply. Moscow benefits from both higher global oil prices and redirected demand, according to analysis from the Carnegie Endowment for International Peace.
Could Chinese refineries resume buying Iranian oil if the conflict ends?
It is possible but significantly harder than before. The U.S. sanctions architecture targeting Chinese end-buyers is now more robust, the precedent of the Shengxing designation has raised the perceived risk, and the 25% tariff on Iran’s trading partners adds another layer of deterrence. However, the financial networks that facilitated these purchases remain largely intact.