China needs security to develop and must modernise its military to make it a Great Wall of Steel, President Xi Jinping says amid mounting tensions with the United States.

Speaking on Monday for the first time in his precedent-breaking third term as head of state, Xi called for China to step up its ability to safeguard national security and manage public security.

"Security is the foundation for development, stability is the prerequisite for prosperity," he said at the closing of the annual parliament session.

The ruling Communist Party is expected to tighten party oversight over security matters, a move that comes after Xi replaced top security officials with his trusted allies.

Xi on Monday also said China must achieve greater self-reliance and strength in science and technology, a call that comes as the US blocks China's access to chip-making equipment and other cutting-edge technologies.

On Taiwan, the self-ruled island China claims as its own and a major producer of semiconductors, Xi said China must oppose pro-independence and secessionist activities and the interference of external forces.

Later on Monday, new Chinese Premier Li Qiang sought to reassure the country's private sector, saying the environment for entrepreneurial businesses would improve and equal treatment would be given to all types of companies.

Li, the former Communist Party chief of Shanghai, was installed as premier on Saturday during the annual session of China's parliament and is tasked with reviving the world's second-largest economy after three years of COVID-19 curbs.

Making his public debut in a media conference, the close ally of Xi said China would take measures to boost jobs and urged officials at all levels to "make friends" with entrepreneurs.

"Developing the economy is the fundamental solution for creating jobs," Li, 63, said in the Great Hall of the People in central Beijing.

Li faces challenges including weak consumer confidence among consumers and private industry, sluggish demand for exports and worsening relations with the United States.

The career bureaucrat talked up his record with the private sector, which has been rattled by a sweeping clampdown targeting industries including internet platforms and private education.

"Indeed, last year there were some incorrect remarks about the development of the private economy, which worried some entrepreneurs," Li said.

"Private entrepreneurs or enterprises will enjoy a better environment and broader space for development ... we will create a level playing field for all kinds of market entities and we will make further efforts to support private entrepreneurs to grow and thrive."

The parliamentary session set a GDP growth target of about five per cent, its lowest goal in nearly three decades, after the economy grew just three per cent last year.

Achieving the target would not be easy, with China facing many difficulties this year, Li said.

Li replaces Li Keqiang, who retired after two five-year terms during which he was seen to be sidelined as Xi tightened his grip on control of the economy.