US warns overdose crisis will spread overseas without action from China

Washington is increasing pressure on Beijing to crack down on illegal supplies of raw materials used to make the synthetic drug fentanyl, warning the deadly overdose crisis sweeping the US could soon spread to Europe and Asia.

Dr Rahul Gupta, the White House drugs tsar, told the Financial Times it is only a matter of time before criminal cartels in China and Mexico expand their highly profitable trade in the drug, which is 50 times stronger than heroin.