A senior Chinese official urged the United States and some other Western countries on Thursday to stop meddling in Hong Kong affairs.

The US and some other countries have been mixing right and wrong, stirring up trouble during the recent violent incidents over the revision of an extradition amendment bill in Hong Kong, said Yang Jiechi, a member of the Political Bureau of the Communist Party of China Central Committee and director of the Office of the Foreign Affairs Commission of the CPC Central Committee, in an interview with Xinhua News Agency.

They also arranged for senior officials to meet leading anti-China figures and supported the illegal activities of extreme, violent protesters with the aim of undermining the prosperity and security of Hong Kong, Yang said.

"We strongly demand the US and some other Western countries abide by international law and basic norms governing international relations, sincerely honor their hands-off promises on Hong Kong affairs and immediately stop meddling in Hong Kong affairs in any form," he said.

Also on Thursday, the Hong Kong Police Force will step up enforcement efforts in handling violent protests, according to Lam Chi-wai, chairman of the Junior Police Officers' Association.

On behalf of over 20,000 front-line officers, Lam expressed confidence in their ability to safeguard law and order in the city.

In a group interview, Lam said extreme, violent acts by radical protesters, whom he called rioters, are likely to continue in coming weeks amid social disputes over the now-suspended extradition bill. He said police have sufficient equipment, personnel and capabilities to maintain the rule of law.

"We are 100 percent confident in safeguarding Hong Kong's law and order, protecting public security and resuming the city's stability as soon as possible," Lam said.

Anyone who participated in unauthorized assemblies broke the law, he said, adding that police would do their utmost to deter violent acts, including using more force. However, Lam stressed that only the minimum necessary force has been used when dispersing illegal protesters.

Hong Kong officers have acted with great restraint compared with law enforcement officers in other places, including the US, Italy and Russia. Even though police officers have been injured, not one bullet from a real gun has been fired against protesters, Lam said.