The Chinese Communist Central Committee, a gathering of about 370 senior officials, endorsed plans last week to “build and improve a legal system and enforcement mechanism to defend national security” in Hong Kong. The communiqué from that meeting was released Tuesday evening. Although it included more than a dozen mentions of Hong Kong, it had few details of what Beijing has in mind.

Beijing’s plans may include national security legislation that could help stifle antigovernment demonstrations. The Basic Law, the mini-constitution that defines Hong Kong’s status, requires that the territory pass its own national security laws, but it has not done so. In 2003, the Hong Kong government abandoned proposed legislation after protests inundated city streets.

Shen Chunyao, the head of a Chinese legislative committee that helps oversee Hong Kong policy, told a news conference in Beijing on Friday that the Chinese leadership also wanted “patriotic education” in Hong Kong to foster stronger loyalty to China, especially among youth and government workers. The communiqué released on Tuesday also called for enhancing “the national consciousness and patriotism of Hong Kong and Macau compatriots.”

Mr. Shen indicated that China may revise how Hong Kong’s chief executive is chosen, but gave no details. The chief executive is currently chosen by a 1,200-member election committee dominated by pro-Beijing groups. There are signs that Beijing’s control of the committee may erode in the coming years unless the rules for choosing its members are changed.

The communiqué went further in saying that the central government “will improve the system and mechanism for the appointment and removal” not just of the chief executive but also of other principal officials in Hong Kong.

The brief Xinhua report about the meeting between Mr. Xi and Mrs. Lam did not mention those initiatives. But it did list four other officials as attending the meeting, including one whose inclusion may indicate Beijing’s perception of a security threat in Hong Kong: Zhao Kezhi, the minister of public security.

The communiqué drew a hard line on what the party perceives as a security threat, saying, “We will resolutely prevent and contain external forces from interfering in Hong Kong and Macau affairs and conducting separatism, subversion, infiltration and destruction activities.”