China has added the United States, Mexico and Canada to a list of countries and regions requiring special licenses to import specific precursor chemicals, as it made adjustments to its management catalog of narcotics-related chemical compounds.

The new rule, effective immediately, was jointly issued on Monday by the Ministry of Commerce, the Ministry of Public Security, the Ministry of Emergency Management, the General Administration of Customs and the National Medical Products Administration.

Thirteen specific types of precursor chemicals have been included in the revised catalog, with the new measures explicitly targeting exports to these three countries. The export of these 13 listed chemicals to the US, Mexico and Canada must be licensed in accordance with relevant management regulations, while exports to other countries and regions do not require such permission, the new rule said.

Precursor chemicals are compounds required in many areas of the chemical and pharmaceutical industries, among others, but are often used illegally to manufacture controlled substances such as narcotics.

According to China's management regulations, when exporting precursor chemicals to specific countries, exporters are required to provide original documentation from competent authorities of the importing country certifying the legal use of these chemicals, or a guarantee document from the importer confirming legal use. These documents are subject to review by the public security and commerce departments.

In April last year, authorities added 24 substances to the catalog of precursor chemicals for export to specific countries. The adjustment took effect on May 1 the same year. The previous list of countries requiring special licenses to import precursor chemicals included Myanmar, Laos and Afghanistan.

On Monday, the Office of China National Narcotics Control Commission also issued a notice reminding exporters to pay close attention to international conventions and the laws of importing countries, especially "high-risk destinations" such as the US, Canada and Mexico.

The exporters have been urged to ensure that foreign clients complete import procedures, in accordance with local regulations, to avoid legal risks involving nonlisted precursor chemicals and equipment that have both legitimate use and the potential to manufacture controlled substances.

The notice further reminded relevant enterprises and individuals to prevent the loss of drug manufacturing materials and nonlisted precursor chemicals and equipment.

Enterprises engaged in the production, sale, transportation, or import and export of nonlisted precursor chemicals and equipment have been urged to establish sound internal management systems, keep relevant records and strictly verify overseas buyers. The notice warned against illegal inducements disguised as "high-value orders" or "sample testing".

If Chinese enterprises or citizens encounter unlawful actions by foreign law enforcement, the notice said they may use legal means to protect their rights and seek help from Chinese embassies and consulates abroad.

The notice also included requirements for postal enterprises, courier companies, logistics companies, international freight forwarders, and other entities and individuals to prevent illegal activities related to drug-manufacturing materials.

China's narcotics control authorities have long regarded the regulation of precursor chemicals as a fundamental measure to curb production of contraband both at home and abroad, keeping strict checks on suspicious transactions and tracing their sources to nip risks in the bud.

The country has also further deepened cooperation with the US on anti-narcotics efforts since last year. A China-US counternarcotics working group was established in January last year, followed by its first meeting and the 10th China-US drug intelligence exchange conference.