The nation's two major Hong Kong affairs authorities on Saturday expressed their firm support to the Hong Kong Special Administrative Region government in regulating mingling activities among separatists from inside and outside the city according to laws.

Spokespeople from the Hong Kong and Macao Affairs Office of the State Council (HKMAO) and the Liaison Office of the Central People's Government in the Hong Kong SAR made the remarks after a key leader of the city's 2014 Occupy Central movement – University of Hong Kong law professor Benny Tai Yiu-ting said when attending a seminar in Taipei, organized by a group advocating "Taiwan independence", that Hong Kong could consider "becoming an independent state".

Tai believes Hong Kong people should decide through a "democratic self-determination".

The HKMAO notices a very small minority of Hong Kong people mingle with separatists from outside the city and openly advocate "Hong Kong independence", the spokesperson said. This has not only demonstrated their separatism agenda, but also contravened China's constitution, the Hong Kong SAR's constitutional document – the Basic Law and relevant local ordinances, a spokesperson from the HKMAO said.

The advocacy also challenged the bottom line of the "one country, two systems" principle, the spokesperson said. We should not turn a deaf ear to or condone such deeds, the spokesperson said.

The office holds the position and supports the Hong Kong SAR government in regulating such mingling activities among separatists within and outside Hong Kong in accordance with laws, the spokesperson said. By doing so, the office believed, the country's sovereignty, national security and Hong Kong's long-term prosperity, stability and fundamental interests can be safeguarded, the HKMAO spokesperson said.

The Liaison Office echoed the pledge. The authority expressed its utmost indignation and strongly condemned Tai's conducts.

This is another wanton conduct of Tai treading on the rule of law after convening the illegal Occupy Central movement, the office stressed.

The office reiterated that "Hong Kong independence" is a serious violation of laws and is "absolutely impossible". All Chinese people including Hong Kong residents have "zero tolerance" to the "Hong Kong independence" advocacy, it said. Such a notion also has "zero room" in China and even elsewhere in the world, the liaison office stressed.

"We hoped people from all sectors in Hong Kong could stand firm in safeguarding the 'one country, two systems' principle and cherish the notable development situation," the office stressed.

It also called on the people of Hong Kong to stand firm against separatism and make their efforts to safeguarding the city's long-term peace and stability.

On Friday, a Hong Kong government spokesman said the government is "shocked" by the remarks made by Tai and strongly condemns them.

The spokesman reiterated that any advocacy of "Hong Kong independence" runs against "one country, two systems" and the Basic Law as well as the overall and long-term interest of society of Hong Kong.