The United States has asked China to crack down on postal shipments of synthetic opioids, which President Donald Trump says are fueling a US drug-abuse crisis, a State Department official said Wednesday.
Because synthetic opioids, such as the highly potent drug fentanyl, are hard to detect in the mail, fighting drug trafficking into the United States has become "a completely different ballgame," said James Walsh of the State Department's Bureau of International Narcotics and Law Enforcement Affairs.
Walsh met this week with Chinese counter-narcotics officials in Cancun, Mexico, on the sidelines of a global conference on drug addiction.
It was a follow-up to conversations between Chinese President Xi Jinping and Trump, who declared the US opioid crisis a national public health emergency in October and said the United States needed to stop "the flood of cheap and deadly fentanyl" coming from China.
Trump and Xi discussed the opioid crisis when they met in Beijing last month.
Ahead of that visit, Chinese officials disputed Trump's claim that most US-bound fentanyl comes from China.
But Walsh said his Chinese counterparts were receptive to working to curb shipments of opioids produced in Chinese labs.
"We've been asking China to get better control on their production, better assistance with monitoring their mail that's being shipped either to Mexico or the United States," he told AFP.
"We've had very good conversations."
Drug overdoses have surged in the United States, killing 64,000 people last year. Most of those deaths were caused by opioids -- a class of drugs that includes prescription painkillers, heroin and synthetics such as fentanyl.
Fentanyl is 50 times more potent than heroin, which has made fighting it a challenge.
"One kilogram can supply a million pills," Walsh said.
"So you can just ship that in a FedEx box."
He said US officials were also in talks with Mexican counterparts on ways to crack down on opioids made in China and trafficked into the United States by Mexican drug cartels.
The traditional tactic of using dogs to sniff out drugs has not worked with fentanyl, which is so powerful it can kill them if they come into contact with it.
"We have a lot of experts working on" new canine training techniques and screening technology, he said.