Fentanyl is a highly addictive synthetic opioid, 50 times more potent than heroin
A Chinese court on Thursday jailed nine people, one with a suspended death sentence, for smuggling fentanyl into the United States, saying this was the first such case the two countries had worked together on.
China has faced US criticism for not doing enough to prevent the flow of fentanyl into the United States, and the issue has become another irritant in ties, already strained by a bruising trade war the two are now working to end.
The announcement of the successful action against the smugglers comes as the two countries are expected to sign an interim trade deal.
Fentanyl is a highly addictive synthetic opioid, 50 times more potent than heroin.
It is often used to make counterfeit narcotics because of its relatively cheap price and it has played an increasingly central role in an opioid crisis in the United States.
Yu Haibin, a senior official with China's National Narcotics Control Commission, told reporters in the northern city of Xingtai where the court case was heard, that Chinese and US law enforcement had worked together to break up the ring, which smuggled fentanyl and other opioids to the United States via courier.
One of the people sentenced by the court was given a suspended death sentence - which in practice is normally commuted to life in jail - and two got life sentences, Yu said.
More than 28,000 synthetic opioid-related overdose deaths, mostly from fentanyl-related substances, were recorded in the United States in 2017, according to the US Centres for Disease Control and Prevention.
US drug enforcement has pointed to China as the source of fentanyl and its related supplies. China denies that most of the illicit fentanyl entering the United States originates in China, and says the United States must do more to reduce demand.
Yu said that the issue of fentanyl was not something any one country could resolve.
"If illegal demand cannot be effectively reduced, it is very difficult to fundamentally tackle the fentanyl issue."
In August, US President Donald Trump accused Chinese President Xi Jinping of not fulfilling a promise to crack down on fentanyl and its analogues.
Yu said China was willing to work with US law enforcement authorities and all other international colleagues to fight narcotics and "continue to contribute China's wisdom and power for the global management of narcotics".