China's countermeasures against the United States in the law enforcement and judiciary sectors are justified and the US side should take responsibility for damaging the foundation of bilateral cooperation in these sectors, experts said.

The Ministry of Foreign Affairs on Friday announced eight countermeasures in response to US House Speaker Nancy Pelosi's visit to Taiwan, who disregarded China's strong opposition.

The countermeasures include suspension of the two-side cooperation on the repatriation of illegal immigrants and legal assistance in criminal matters, and cooperation against transnational crimes and in the sector of counternarcotics.

Huang Jin, deputy head of the China Law Society, said the suspended cooperation areas are established based on bilateral memorandums and do not involve international treaties and agreements or documents that require the approval of the legislature.

"The establishment of the cooperation took plenty of time and effort from both sides. Since the two sides have the will to cooperate, then both sides need to show their sincerity. Pelosi's visit to Taiwan broke the base of cooperation in these areas, making it hard to carry on. It's justified to suspend these areas on the basis of safeguarding China's national sovereignty," Huang said.

Huang added China's decision on the scope and areas of the suspension was made after long consideration, with China ultimately concluding the problems of drug trafficking, immigration, transnational crime and the judicial field are where the US needs more support from China.

"The US has always chosen to cooperate with us only in the areas they want to cooperate with. Now, we can take the initiative to suspend cooperation in the areas they want to cooperate with, so as to have a sanction effect," he said.

At the same time, these measures serve as a warning to other countries that want to maintain ties with China while following the US in inappropriate moves, he added.

The chairman of the United Kingdom's House of Commons' foreign affairs committee, Tom Tugendhat, was reportedly planning to lead a delegation to visit Taiwan later this year.

The countermeasures were taken by the Chinese government against the US's gross interference in China's Taiwan affairs, which cause serious damage to China's sovereignty and territorial integrity, said Chen Xiangyang, director of the Office of the Study Center for Holistic Approach to National Security.

The countermeasures also show China-US relations are deteriorating, and the blame lies entirely with the US. Behaviors from the US including Pelosi's visit to Taiwan and her association with "Taiwan independence" forces, as well as the US government's repeated shirking of its responsibilities for Pelosi's visit and making accusations against China's countermeasures, threaten China's core interests, Chen said.

Even though some areas may have a larger impact on China in the short term, they are tolerable when compared with China's core interests of safeguarding its sovereignty and territorial integrity, he added.

Besides, due to the inactive attitude of the US, cooperation is limited in these sectors, thus the impact is limited for China, he said.

Taking the anti-narcotic moves as an example, the suspension of China-US anti-drug cooperation could impact the fight against transnational drug crimes. It has a greater impact on the US, as its drug abuse problems are far more serious, he said.

China has listed the whole category of fentanyl as a controlled substance in May 2019 as a measure to fight drug crimes. But the US included the Institute of Forensic Science of China's Ministry of Public Security and the National Narcotics Laboratory, both important institutions responsible for the detection and control of fentanyl, to its "Entity list" for sanctions in May 2020.

As for the resumption of cooperation in the future and when it can be resumed, it depends on how the US behaves on issues concerning China's core interests such as the Taiwan question, and whether the US respects China's national dignity, Chen said.