From the Key Findings: " 'China remains the primary country of origin for illicit fentanyl and fentanyl-related substances trafficked into the United States:' In 2019, China fulfilled a pledge to the United States and placed all forms of fentanyl and its analogues on a regulatory schedule. Nevertheless, illicit fentanyl from China remains widely available in the United States. Chinese traffickers are using various strategies to circumvent new regulations, including focusing on chemical precursors, relocating some manufacturing to India, rerouting precursor shipments through third countries, and leveraging marketing schemes to avoid detection. [...]  'Since China's government scheduled fentanyl, the amount of finished fentanyl shipped directly from China to the United States has declined, while the amount shipped from Mexico has increased:' The U.S. Drug Enforcement Administration (DEA) assesses Chinese traffickers have shifted from primarily manufacturing finished fentanyl to primarily exporting precursors to Mexican cartels, who manufacture illicit fentanyl and deliver the final product. U.S. law enforcement has seen a growing trend of Chinese nationals, in both Mexico and the United States, working with Mexican cartels. [...]  'Chinese brokers are laundering Mexican drug money through China's financial system:' Chinese money launderers are using financial technology, mobile banking apps, and social media to evade authorities.  'Cooperation between the United States and China remains limited:' U.S. law enforcement agencies have established working groups, conducted high-level meetings, and shared information with their Chinese counterparts, which has led to the dismantling of a few illicit fentanyl networks."
U.S.-China Economic and Security Review Commission: https://www.uscc.gov/