A senior White House official on Thursday said he believed China was “absolutely committed” to cooperating with the United States to curb illicit fentanyl , a drug which has played a major role in the US opioid crisis. “I am absolutely convinced the Chinese, starting with President Xi [Jinping] down through the Minister of Public Security Zhao [Kezhi], are absolutely committed to doing this,” Jim Carroll, director of National Drug Control Policy, an office colloquially referred to as “drug tsar”, said in Beijing after meeting his Chinese counterparts. “I fully believe that what we learned on this trip is that the Chinese government, the Chinese people, are committed to this issue, both to save lives in the United States, but also to save lives in China. I believe that.” Carroll, accompanied by acting commissioner for US Customs and Border Protection Mark Morgan and chief postal inspector Gary Barksdale, described the visit as “groundbreaking”. US officials would have routine conversations and intelligence sharing at a higher level with Chinese authorities to ensure the two sides were “truly eradicating” traffickers, Barksdale said. Morgan said he was encouraged by Chinese plans to build more laboratories, and that the US would be sharing data from new pollen signature chemical tests that can help identify the countries of origin of fentanyl samples. Those caught in fentanyl crisis say solutions lie at home, not in China US officials said China was the main source of illicit fentanyl, a cheap, opioid painkiller 50 times more potent than heroin, and related substances trafficked into the United States, much of them through international mail. Beijing has cited US statistics to deny that most of the fentanyl entering the United States originates in China. This month, Liu Yuejin, vice-commissioner of the China National Narcotics Control Commission, said the two countries had only limited cooperation to stop fentanyl smuggling. The row over fentanyl comes as the US is in the middle of a harsh trade war with China, and some experts believe that may have frustrated meaningful cooperation on trafficking. The US treasury department imposed sanctions on three Chinese men accused of illegally trafficking fentanyl in August, but US officials have been frustrated that China has not arrested them. The National Institute of Drug Abuse reported this year that 130 people die every day in the US after overdosing on opioids, which include prescription pain relievers, heroin and synthetic drugs such as fentanyl. In August, US President Donald Trump accused Xi of not living up to his pledges to crack down on the drug. China called that “blatant slander” and said the US needed to do more at home to fight fentanyl abuse and reduce demand for the drug.