Chief Executive John Lee on Monday quoted a top Beijing official on Hong Kong affairs as saying that the SAR needs to stand ready to tackle hidden forces seeking to destroy national security or undermine the city’s social stability.

Lee was speaking to reporters after flying back from Beijing, where he attended the opening of the National People's Congress session.

He said during a meeting with the director of the Hong Kong and Macau Affairs Office, Xia Baolong, over the weekend, the official reminded him that national security risks still exist in the SAR, and the government must stay alert.

"We will do a good job of risk assessment, and we'll step up [our work on] intelligence gathering, to ensure that we've done it perfectly," Lee said.

"We will definitely crack down on any [forces] trying to undermine national security or breach the peace of Hong Kong society, or [hurt] Hong Kong's overall interests – and hold them legally responsible under the law."

The CE also quoted Xia as saying he recognised the work of the SAR administration over the past eight months, while praising the different sectors for being more proactive in integrating into national development plans like the Greater Bay Area and the Belt and Road initiatives.

Lee added that President Xi Jinping also expressed his concern and encouragement for Hong Kong as it seeks to boost the economy and improve people's livelihoods.