The central government has an unquestionable role to maintain national security, including that in the Hong Kong Special Administrative Region, director of the State Council's Hong Kong and Macao Affairs Office Zhang Xiaoming stressed on Friday.

He fielded questions from the press at the two-session's "ministers' passage" a week after the central government issued an official letter to voice support of the HKSAR government's ban on the pro-independence Hong Kong National Party, and at the same time requested the chief executive submit a report on the issue.

It is impossible for the central government to turn a blind eye to acts that jeopardize national security in Hong Kong, as the SAR is an inalienable part of China, Zhang said.

The official letter not only indicates the central government's firm support to the HKSAR government's decision regarding the HKNP, but also shows its basic standpoint – to safeguard national reunification and territorial integrity.

The advocacy of Hong Kong independence will destroy the implementation of the "one country, two systems" principle and is against the mainstream will of Hong Kong people, Zhang added.

Despite queries over the central government's rare request for the Chief Executive to submit a report, Zhang said the move is "appropriate" and "in accordance with the laws".

"It is not interfering or weakening the SAR's high degree of autonomy," Zhang said.

The HKNP is the city's only political party explicitly advocating "Hong Kong independence". Hong Kong's Secretary of Security John Lee Ka-chiu in September announced the prohibition of the HKNP in accordance with the city's Societies Ordinance.