The government has hit back at comments by some US groups and lawmakers on national security cases in Hong Kong.

In a statement on Tuesday, it said it "strongly disapproved and firmly rejected the scandalising of the criminal justice process of the HKSAR, including cases concerning the Hong Kong National Security Law, by some groups and members of the United States Congress."

It said all defendants are entitled to a fair trial, and their professions, political beliefs or background do not affect the way the cases are handled.

The statement also said the Basic Law guarantees that the courts here exercise judicial power independently, free from any interference, and any attempt to interfere with the judicial proceedings is a blatant act undermining the rule of law of Hong Kong.