And, although the Chinese authorities don't officially accept that most fentanyl is produced in China, they have taken some action. The US believes China to be the main source of illegal batches of synthetic drug fentanyl , which is at the heart of an opioid - abuse epidemic in the US . In August , US President Donald Trump claimed that the drug is entering the US from China via the postal system . However , Yu Yang from China 's National Narcotics Control Commission described Trump 's comments as " unacceptable " and " irresponsible " . London School of Economics ' International Trade Policy Institute head , John Collins , has called for broader resolution of the US crisis , while China also believes the US should address demand for drugs by its citizens .
The US believes China to be the main source of illegal batches of synthetic drug fentanyl , which is at the heart of an opioid - abuse epidemic in the US . In August , US President Donald Trump claimed that the drug is entering the US from China via the postal system . However , Yu Yang from China 's National Narcotics Control Commission described Trump 's comments as " unacceptable " and " irresponsible " . London School of Economics ' International Trade Policy Institute head , John Collins , has called for broader resolution of the US crisis , while China also believes the US should address demand for drugs by its citizens .