May 11, 2026: For most of the last two decades, China has preserved a delicate balance in its military relationship with Iran, often offering indirect assistance instead of arms sales.

That approach is now drawing renewed attention after American officials said intelligence agencies were assessing whether China may have shipped shoulder-fired missiles to Iran in recent weeks. The American President Trump insisted that he would impose an additional 50 percent tariff on Chinese goods if the calculation proves accurate. China has denied the claim, calling it pure fiction and has sworn to purposefully retaliate if the American government goes through with tariffs.

The American bureaucrats said the information obtained by American intelligence agencies was not definitive. But if proven true, it would be a substantial tactical change in the way China supports its closest strategic partner in the Middle East.

Chinese arms sales to Iran exploded in the 1980s and have all but vanished in the last decade to comply with a United Nations embargo and American sanctions. Chinese support for Iran in recent years has instead come in the form of components that could be used in both civilian technologies as well as missiles and drones. China has a major stake in the crisis in Iran. About a third of its total crude oil imports come from the Persian Gulf.

This is how China’s military support for Iran has evolved over the years. The 1980s were the Surge Years. The outbreak of the Iran-Iraq War in 1980 coincided with major market reforms in China when its leader at the time ordered state-owned companies to wean themselves off government support and instead seek commercial profit.

Chinese state-run defense companies were suddenly empowered to export their wares. That resulted in a deluge of Chinese missiles, fighter jets, tanks, armored vehicles and assault rifles being sold to Iran starting in 1982 and climaxing in 1987, all during the Iran-Iraq War.

At the same time, China sold even more arms to Iraq, resulting in a situation in which the two warring sides clashed with each other using the same Chinese weapons.

The American government opposed China’s arms sales to Iran, particularly Silkworm anti-ship cruise missiles. Iran used the missiles in attacks in Kuwaiti waters in 1987 that struck an American-owned tanker and an American-registered tanker.

The Americans responded by reducing exports of some high-technology products to China. While China denied selling arms directly to Iran, they said it would do more to prevent its military exports from reaching Iran through intermediaries.

The 1990s: Technology Transfers. Following the war, Iran set out to develop its own military-industrial base with the help of China. One of its key products was the Noor anti-ship cruise missile, which had been reverse-engineered through purchases of Chinese C-802 cruise missiles.

The Chinese performed a major role in supporting Iran’s military modernization for decades, especially in developing Iran’s missile capabilities. Iran also received help from China in building missile-production facilities and even in constructing a missile test range east of the Iranian capital.

Under American pressure to curtail its sale of finished weapons, particularly missiles, to Iran, China began increasing exports of machine tools and components that could be used for both military and civilian purposes.

The 2000s: Dual-Use Technologies. In 2006, the United Nations imposed sanctions on Iran’s nuclear and ballistic missile programs. China voted in favor of the decision and largely turned away from new, formal arms contracts with Iran.

The shift was as much about regional strategy as it was about international law. Starting in the mid-2010s, China began deepening its strategic relationships with Gulf countries including Saudi Arabia and the United Arab Emirates, traditional rivals of Iran, as well as Qatar.

China continued to supply Iran with dual-use technologies and materials that have helped it amass an arsenal of missiles and drones. That included chemicals used to produce fuel for ballistic missiles and components for drones, such as radio frequency connectors and turbine blades

China was still a crucial type of support, given Iran’s reliance on ballistic missiles and drones to attack American and Israeli forces and other countries in the region.

The American Treasury Department imposed sanctions on Chinese and Hong Kong front companies it says were set up to source parts and ingredients for ballistic missiles and drones for Iran.

Suspicions are also growing that Iran is using its access to China’s BeiDou satellite navigation system, an alternative to the American owned Global Positioning System, for military purposes. Last month, an American congressional agency said BeiDou may have been used to direct Iran’s drone and missile strikes across the Middle East.