The new head of Beijing's liaison office in Hong Kong on Saturday said the SAR has entered a "new era" following the enactment of the National Security Law, as he told the city to foster long-term stability through high-quality development.

In his first major public speech since taking up his new position last month, liaison office director Zhou Ji underscored the need to defend the foundation of the rule of law by fully implementing national security legislation in the city.

"We must make sure there's a high-level of security to safeguard high-quality development," Zhou said.

"Without a high level of political, economic and social security, there's no way we can take forward high-quality development," he stressed.

The official said Hong Kong’s future will depend on its ability to move with the times to bring about high-quality development.

"Following the in-depth implementation of the National Security Law, Hong Kong has entered a new stage of development. It is currently striving to seek economic growth, pursue development, undergo reforms, advance infrastructure and improve people's livelihoods," Zhou said.

"In the new stage of One Country, Two Systems, we must take the initiative to assess, adapt and seek change, and promote Hong Kong's long-term prosperity and stability through high-quality development."