Secretary for Security Chris Tang said a 20-year jail sentence given to Jimmy Lai showed that any act endangering national security, in particular colluding with foreign forces, is "very serious".

"The court's judgement illustrates that the rule of law in Hong Kong is robust. Criminal acts will never be tolerated. And no one is above the law," Tang told a press briefing.

"[Lai's case] also has nothing to do with press freedom. If anything, the defendant has used journalism as a guise to harm our country and Hong Kong over the years."

The Apple Daily founder and eight co-defendants were given jail sentences on Monday.