Individuals convicted of national security offences would not receive a sentence reduction under normal circumstances, Chief Executive John Lee said on Tuesday, after authorities reportedly decided against granting an early release to an inmate jailed for inciting secession.

It is understood that Ma Chun-man did not receive an early release, normally granted for good behaviour in prison, due to amended rules under the new homegrown Article 23 national security legislation.

Prison rules now specify that "a prisoner must not be granted remission... unless the [Commissioner of Correctional Services] is satisfied that the prisoner's being granted remission will not be contrary to the interests of national security".

Lee stressed people should not test the law and expect a remission when offences endangering national security are involved.

"No one should attempt to do anything to endanger national security, because normally there's no remission of sentence [for those offences]," he said ahead of the weekly Executive Council meeting.

"The Commissioner of Correctional Services will follow the law in making such decisions. When someone is aggrieved by the decision, they have legal means and can seek the court's view on how the matter should be dealt with."

Ma, who was dubbed “Captain America 2.0” for dressing up as the comic book hero during the anti-government protests in 2019, was reportedly due to be released on Monday for good behaviour.

He was originally sentenced to five years and nine months in prison, but had his term later reduced to five years following an appeal.