China says it has introduced a set of "trial outlines" on its armed forces military operations that are not war. Taiwan media cite experts' view calling for vigilance against the move.

China's state-run Xinhua News Agency recently reported that President Xi Jinping, who is also the chairman of the Central Military Commission, signed an order to promulgate the outlines, which take effect on Wednesday.

Details of the outlines are not disclosed. But Xinhua says the outlines, composed of 59 articles, will address emergencies and aim to "safeguard national sovereignty, security and development interest and world peace and regional stability."

It adds that the outlines "serve as a legal base for military operations other than war."

A Taiwanese newspaper, The Liberty Times, on its Tuesday online edition quotes an expert as saying Taiwan must be cautious because what China calls "military operations" could be used as a cover-up when it wages an act of war.

A Chinese foreign ministry spokesperson told reporters on Monday that "certain countries call the Taiwan Strait 'international waters' in order to find a pretext for manipulating issues related to Taiwan and threatening China's sovereignty and security." He said, "China is firmly against this."

Observers say the remarks may indicate China's possible stance that it does not regard the strait as "international waters." They say China apparently aims to create an environment where international law will not be applied to a contingency involving Taiwan.