WASHINGTON, July 16 (Reuters) – U.S. President Donald Trump said on Wednesday that he thinks China will soon sentence people to death for fentanyl manufacturing and distribution, as he offered fresh optimism about the prospects of a deal with Beijing on illicit drugs.

The drug trade has joined a range of economic and security issues as a major flashpoint in the relationship between the countries in recent years.

Washington accuses Beijing of failing to stem to curb the flow of precursor chemicals for fentanyl, a leading cause of U.S. overdose deaths. Beijing has defended its drug control record and accused Washington of using fentanyl to “blackmail” China.

Trump imposed 20% tariffs on Chinese imports over the issue in February, and they have remained in effect despite a fragile trade truce reached by both sides in Geneva in May.

“I think we’re going to work it out so that China is going to end up going from that to giving the death penalty to the people that create this fentanyl and send it into our country,” Trump said. “I believe that’s going to happen soon.”

The Chinese embassy in Washington did not immediately respond to a request for comment.

Trump spoke before he signed the HALT Fentanyl Act, a law increases prison terms for drug offenses involving fentanyl-related substances. The event was attended by family members of people who had died from fentanyl overdoses.

More than 450,000 Americans have died of synthetic opioid overdoses over the past decade, with millions more addicted.

Trump has been working to lower tensions with Chinese leader Xi Jinping ahead of a potential in-person meeting later this year.

“I think China’s been helping out,” Trump told reporters earlier on Wednesday. “Since I came here we’re talking to them and they’re making big steps… They want to do something. We’ll see what happens.”

China has balked at some of Washington’s demands, which include publicizing the crackdown on fentanyl precursors on the front page of the Communist Party mouthpiece People’s Daily and tightening regulation of specific chemicals.

But Beijing has also taken a series of actions on counter-narcotics in recent weeks. These included adding two more fentanyl precursors, 4-piperidone and 1-boc-4-piperidone, to a list of controlled chemicals starting on Sunday.

Last month, Chinese state media that immigration officials have seized more than 2 tons of drugs and arrested 262 suspects for drug smuggling so far this year.

Chinese officials also said they had prosecuted more than 1,300 people and arrested over 700 more nationwide for drug-related money laundering offences between January and May this year, a 2.1% year-on-year increase.

A court in the southeastern province of Fujian last month handed a suspended death sentence to former drug control official Liu Yuejin for bribery, state media reported.