The following is the Feb. 1, 2023, Congressional Research Service In Focus report, Chinese Nuclear and Missile Proliferation.
From the report
The U.S. government has continued to express concerns about China’s record concerning the proliferation of nuclear- and missile-related technologies to other countries, with more recent focus on the threat of Chinese acquisition of U.S.-origin nuclear technology. Official U.S. government reports indicate that the Chinese government has apparently ended its direct involvement in the transfer of nuclear- and missile-related items, but Chinese-based companies and individuals continue to export goods relevant to those items, particularly to Iran and North Korea. U.S. officials have also raised concerns about entities operating in China that provide other forms of support for proliferation-sensitive activities, such as illicit finance and money laundering.
China did not oppose new states’ acquisition of nuclear weapons during the 1960s and 1970s, the Department of State wrote in a declassified January 1998 report to Congress. According to a 1983 National Intelligence Estimate (NIE), China had exported “nuclear materials since 1981” that were not subject to International Atomic Energy Agency (IAEA) safeguards. Beijing did so “mainly to earn hard currency,” the estimate assesses, explaining that the
Chinese became aware in 1979 that they had insufficient resources for their initially grandiose modernization program and that they needed to generate more revenue through expanded foreign trade. Accordingly, the State Council directed its subordinate ministries in late 1979 to begin selling surpluses.
Consequently, according to the NIE, Beijing ended its “abstention from commercial trade in conventional arms and nuclear materials.” During the 1980s and 1990s, China transferred nuclear and missile technology to other countries’ weapons programs. China provided assistance to Pakistan’s nuclear weapons program and engaged in nuclear cooperation with Iran. Beijing exported missiles to Pakistan, Saudi Arabia, and Iran. (For more information, see CRS Report RL33192, U.S.-China Nuclear Cooperation Agreement, by Mark Holt, Mary Beth D. Nikitin, and Paul K. Kerr.)
According to U.S. government reports and official statements, China significantly curtailed its nuclear- and missile-related transfers during the 1990s; Beijing also committed to improving its export controls. For example, the 1998 State Department report cited above noted China’s 1996 pledge to refrain from assisting unsafeguarded nuclear facilities and 1997 changes to Chinese nuclear export policy, as well as other Chinese nonproliferation efforts.
The United States has extensive nuclear cooperation with China, which is governed by a civil nuclear cooperation agreement, renewed in 2015. (See CRS Report RL33192, U.S.-China Nuclear Cooperation Agreement.)
The above-described changes in Chinese behavior took place after the two governments concluded their first nuclear cooperation agreement in 1985. Laws subsequently adopted by Congress required, as a condition for U.S. implementation of the agreement, the President to submit to Congress certain nonproliferation-related certifications, as well as a report about Beijing’s “nonproliferation policies and practices.” President William Clinton stated in a January 1998 letter to Congress that China had “made substantial strides in joining the international nonproliferation regime, and in putting in place a comprehensive system of nuclear-related, nationwide export controls,” since concluding the 1985 agreement.
Beijing acceded in 1992 to the Nuclear Nonproliferation Treaty (NPT) as a nuclear-weapon state (NWS) and has voluntary IAEA safeguards on its civil reactors. The treaty defines NWS as those that exploded a nuclear weapon or other nuclear explosive device prior to January 1, 1967: China, France, Russia, the United Kingdom, and the United States. All other NPT states-parties are nonnuclear-weapon states. According to the treaty, a NWS is not to transfer nuclear weapons to “any recipient whatsoever” or to “in any way … assist, encourage, or induce any” nonnuclear-weapon state “to manufacture or otherwise acquire nuclear weapons.”
China is also a participant in the Nuclear Suppliers Group (NSG)—a multilateral control regime for nuclear-related exports. The Missile Technology Control Regime (MTCR) performs an analogous function for missiles and related items. China is not an MTCR partner but has agreed to adhere to the regime’s export guidelines.
The Chinese government continues to express support for the international arms control and nonproliferation regime. According to a July 2019 Chinese government publication titled China’s National Defense in the New Era, “China actively participates in international arms control, disarmament and non-proliferation” and “objects to arms race and strives to protect global strategic balance and stability.” Similarly, Fu Cong, Director General of the Department of Arms Control of China’s Ministry of Foreign Affairs, stated during the December 9-10, 2020, 16th Asian Senior-Level Talks on Non-Proliferation that “China is ready to enhance non-proliferation policy Chinese Nuclear and Missile Proliferation exchanges and cooperation with all countries, including the incoming U.S. administration.”
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