By Tan Ee Lyn

HONG KONG, July 18, 1997 (Reuter) - Hong Kong, recently unified with China, handed police wide discretionary powers Friday to ban protests or political groups on "national security" grounds.

The government issued guidelines allowing the chief of police to ban gatherings if they threaten China's "national security," promote independence for Tibet or Taiwan, or cause public disturbance.

Police can also ask the government's security chief to cancel the registration of a society due to national security.

The guidelines expand on laws enacted by Hong Kong's Chinese-appointed legislature hours after Britain handed this former colony of 156 years back to China on July 1.

The laws, pushed through by Hong Kong's new leader Tung Chee-hwa at China's behest, set curbs on protests and the registration of parties and included the concept of "national security." The concept was not defined at the time.

The latest development came hard on the heels of a government move that froze a set of labor rights laws, drawing strong attacks from international and local labor groups.

The International Confederation of Free Trade Unions called it a slap in the face and a breach of China's promises on labor standards.

Tung's government issued a statement Friday putting the fine print on the curbs, which have sparked criticism locally and abroad for rolling back rights in this bustling capitalist metropolis of 6.4 million people.

The government said the police chief could invoke national security if he considered it necessary "in order to safeguard the territorial integrity and independence" of China.

"In coming to his decision, the Commissioner of Police will take into consideration...whether or not the declared purpose of the notified public meeting or procession is to advocate separation from the People's Republic of China, including advocacy of the independence of Taiwan or Tibet," it said.

A meeting or protest could also be banned on grounds of national security if police thought it "likely to cause or lead to an imminent breach of the peace."

Before Hong Kong's handover, people needed only to notify the police if they wished to hold protests, not seek permission.