5 Things to Know About China-Iran Security Cooperation
China and Iran both seek to counter American influence in the Middle East and have long cooperated to further that shared goal. China provides Iran with inputs for its ballistic missile program, helps Tehran circumvent international sanctions by purchasing Iranian oil, and has provided limited support to the Iran-backed Houthi rebels in Yemen. Together with Russia, both countries regularly conduct joint naval exercises, thereby boosting Beijing’s maritime presence in the region. This teamwork continued as Washington pursued diplomacy with Tehran. However, after Israel began targeted strikes on Iran on June 13, China did not extend military assistance to its partner.
- China has long supported Iran’s ballistic missile program and backed it with dual-use industrial inputs for missile production.
China recognized the regime in Iran shortly after the 1979 Islamic Revolution and provided missiles and arms in the 1980s throughout the U.S. embargo. At least one of the missile systems Tehran used to target U.S. forces in Iraq in 2020 included technology from this long-term partnership with China. In the spring of 2023, Iranian officials negotiated in Beijing and Moscow to replenish Tehran’s stores of ammonium perchlorate, a precursor for ballistic missile solid propellant. In January 2025, two Iranian cargo vessels sailed from China with more than 1,000 tons of sodium perchlorate, a precursor for ammonium perchlorate. One vessel arrived in Iran in February, and the other arrived on March 29. The Treasury Department sanctioned entities in China and Iran involved in the procurement of ballistic missile propellant precursors and unmanned aerial vehicle components in April. The Wall Street Journal reported in early June on additional shipments of ballistic missile propellant ingredients.
- China has conducted regular maritime cooperation with Iran, boosting Beijing’s presence in the Persian Gulf, but did not extend security assistance after June 13.
In 2016, Chinese President Xi Jinping conducted a state visit to Iran and signed agreements that laid the diplomatic groundwork to upgrade relations by 2021. Maritime cooperation was a recurring mechanism for improving military-to-military relations. The People’s Liberation Army (PLA) invited Iranian defense leadership in 2019 to discuss furthering defense relations and observe naval facilities and vessels. China, Iran, and Russia held the joint maritime exercise series known as Sea Security Belt in 2019, 2022, 2023, 2024, and March 2025. These exercises occurred even as Iran harassed vessels in 26 incidents from January 2021 to July 2023. As the Trump administration sought direct negotiations with Iran, the PLA signaled after the March 2025 exercise that “China is willing to actively engage in maritime security cooperation with all parties, and make new contributions to world and regional peace and stability.” China did not demonstrate a maritime response in support of Iran after June 13 despite its growing capacity to project naval power.
- China is the largest importer of Iranian oil, helping Tehran bypass sanctions and generate state revenue while increasing Beijing’s role in Gulf maritime security.
China has steadily increased its imports of Iranian oil since February 2021, when China committed to $400 billion of foreign direct investment in Iran over 25 years in return for discounted oil. The agreement reportedly included unspecified security cooperation commitments. Months later, the Chinese-led Shanghai Cooperation Organization (SCO) approved Iran as a member state. China is now the largest importer of Iranian oil, providing an “economic lifeline” for Tehran as it faces American and international sanctions, said U.S. Treasury Secretary Scott Bessent in March. More than 90 percent of Iranian oil exports in 2024 and 2025 were destined for China. In May 2025, Washington sanctioned multiple Chinese “teapot” refineries, which purchase and refine what the Treasury Department described as hundreds of millions of dollars’ worth of Iranian crude oil. On June 14, the SCO issued a statement condemning Israel for attacking Iran. Xi later issued a four-point proposal calling for a ceasefire. China likely seeks de-escalation to ensure its energy flows from Iran and the Gulf.
- China has provided material and intelligence support to the Iran-backed Houthis.
With explicit language that marked a change from previous years, the U.S. Department of Defense stated in its 2024 annual report to Congress on Chinese military and security developments that “Houthi procurement networks rely on PRC-based suppliers to supply and facilitate shipments of dual-use components and equipment for Houthi missile and UAV manufacturing.” China has also provided targeting data for Houthi strikes against U.S. interests. In April, The Wall Street Journal reported that Chinese satellite firm Chang Guang Satellite Technology — which has publicly acknowledged its ties to Chinese military intelligence and was sanctioned for supporting the Russian mercenary Wagner Group — provided satellite data to the Houthis, assisting with their targeting of U.S. interests. Washington raised the issue with Beijing prior to the declared ceasefire with the Houthis on May 6.
- Chinese, Iranian, and Russian trilateral consultations occurred throughout the spring of 2025 as Washington sought direct negotiations with Tehran.
After the Trump administration took office, Iran increased its engagement with China and Russia. Beijing, Moscow, and Tehran held trilateral consultations in March 2025 in the Chinese capital, where China issued a five-point proposal calling on Iran to uphold its commitment not to develop nuclear weapons and urging all parties to resume negotiations. Iran rejected direct negotiations with Washington by the end of the month as Chinese and Russian naval forces concluded their exercise with Iran and a ballistic missile propellant precursor shipment arrived in Iran. China, Russia, and Iran held a second trilateral consultation in Moscow days before the United States and Iran held their first direct talks on April 12. This occurred as the Department of State engaged with its Chinese counterparts regarding China’s satellite support to Houthi targeting of U.S. interests. Iran sought to expand its preferred trilateral framework in April, and China acknowledged that it viewed Iran as a partner “to safeguard multilateralism.”