WASHINGTON: The first joint meeting of a US-China working group on fentanyl precursor chemicals will be held on Tuesday in Beijing, a senior US official said on Sunday.

“This is a key part of the implementation of our bilateral cooperation on this effort,” the US official told reporters.

Fentanyl is a leading cause of drug overdoses in the United States. The US has said that China is the primary source of the precursor chemicals synthesized into fentanyl by drug cartels in Mexico. China denies this.

The official added that the United States has information that China started action against Chinese precursor chemical companies around the time of the summit of US President Joe Biden and Chinese President Xi Jinping last November.

The United States will pursue law enforcement actions and impose controls on the precursors and the meeting is a pivotal moment for the issue, the official said.

Top Chinese and US officials held candid talks in Bangkok aimed at lowering tensions between the United States and China, ahead of an expected call between Biden and Xi to be held this spring.

Ties between the two countries have been tense in recent years over a range of issues including the origins of COVID-19, trade tariffs, Taiwan and human rights.

Biden and Xi discussed efforts to reduce the flow of fentanyl at a summit in California last year. The US has already made fewer seizures of illicit chemicals used to make fentanyl at US airports after China moved to shut down companies that make them.

China has started some conversations with Mexico about the issue, the US official said on Sunday. “It is really important that this is a multilateral issue,” the official said.

Earlier this month, interactions between China and the US have included a meeting in Washington between senior Chinese official Liu Jianchao and Secretary of State Antony Blinken. In addition, US Commerce Secretary Gina Raimondo held a phone call with China’s commerce minister, Wang Wentao, and military talks resumed after a long freeze.