China's central authorities have voiced support for the Hong Kong Special Administrative Region (HKSAR) over its lawful verdict in the Jimmy Lai case and pledged continued efforts to safeguard national security.

Lai, an instigator of anti-China riots in Hong Kong, was found guilty on two charges of conspiring to collude with external forces and a charge of conspiracy to publish seditious materials, according to the verdict handed down by the High Court of the HKSAR on Monday.

Court proceedings presented substantial evidence showing that Lai engaged in activities endangering national security, played a key role in the unrest that gripped Hong Kong, and acted as a pawn of external forces, said an article released by the Hong Kong and Macao Work Office of the Communist Party of China Central Committee on its social media account after the verdict.

Safeguarding national sovereignty, security and development interests is the highest principle of the "one country, two systems" policy, the office said, adding that the HKSAR bears a constitutional responsibility to safeguard national security.

When asked to comment on the verdict, Chinese foreign ministry spokesperson Guo Jiakun said at a regular news briefing that China deplores and firmly opposes certain country blatantly making false accusations against Hong Kong's judicial affairs.

"Hong Kong upholds the rule of law. The central government firmly supports Hong Kong in safeguarding national security and punishing crimes that endanger national security in accordance with the law," Guo said.

Central government agencies in Hong Kong also made statements on Monday in support of the verdict.

A spokesperson of the Liaison Office of the Central People's Government in the HKSAR said this is the first case in Hong Kong involving charges of colluding with external forces to endanger national security under the national security law in Hong Kong.

The verdict reaffirmed the zero-tolerance stance on acts and activities endangering national security, and served as a stern warning to all anti-China elements destabilizing Hong Kong that all national security offences will be punished under the law, according to the spokesperson.

A spokesperson for the Office for Safeguarding National Security of the Central People's Government in the HKSAR said that safeguarding national security is a top priority in any country.

The office will work with the HKSAR to fully and accurately implement laws for safeguarding national security, punish crimes endangering national security in accordance with the law, and resolutely crack down on acts and activities of external forces interfering in the trial of national security cases and undermining the rule of law in Hong Kong, according to the spokesperson.

A spokesperson for the Commissioner's Office of the Chinese Foreign Ministry in the HKSAR strongly denounced and firmly opposed smearing remarks about the verdict on Lai's case from Britain, Australia, the United States, Germany and the European Union, as well as certain politicians.

The case is an internal matter of the HKSAR, said the spokesperson, urging relevant countries and politicians to stop interfering in Hong Kong affairs, which are China's internal affairs.