BEIJING — China will roll out new steps to “safeguard national security” in Hong Kong after months of antigovernment protests that have destabilized the semiautonomous city, the Chinese Communist Party leadership announced on Thursday.

The vague yet potentially far-reaching proposal for Hong Kong was announced at the end of a four-day meeting of the party’s Central Committee, which brings together about 370 senior officials to decide the direction of party policy around once a year.

The official summary of the meeting, released by Xinhua, the official Chinese news agency, contained few details of that and other proposals intended to defend the authority of the Communist Party and its leader, Xi Jinping, and to improve decision making. Details may come out in documents and speeches released days or weeks later.

Here are key points from the summary.

Hints of a new plan to quell the Hong Kong protests.

The most eye-catching language was about Hong Kong, where for some 21 weeks protesters have challenged the Beijing-backed government, demanded democracy and denounced China’s growing hold over the city, a former British colony that maintains its own laws and freedoms.