China relaxed its stringent zero-Covid restrictions in several cities after public protests and stepped up security across the country on Thursday as it braced for next week's high-profile funeral of former president Jiang Zemin who died a day earlier.

Flexible measures were implemented across China to ensure people's livelihoods amid the cold front, the official media reported.

After protests against zero-covid lockdowns, China's top industrial and business hub Guangzhou lifted temporary restrictions in some regions and officially allowed qualified close contacts to be quarantined at home instead of in temporary shelters.

Such announcements relaxing the Covid curbs were announced in Beijing, Shijiazhuang, Taiyuan besides several other cities, the official media reports said.

Beijing witnessed mixed lockdown covid policies. While some buildings went into lockdown on Thursday, all over the city people complained that many of the Covid testing centers have been closed following complaints of people getting infected while standing in long lines.

Vice Premier Sun Chunlan, who headed the anti-covid fight for the past three years, has signalled a new chapter in the country's pandemic response with small, progressive refinements to restrictive measures, in a sign the zero-Covid policy may be gradually phased out.

In a meeting with experts from the National Health Commission on Wednesday, Sun also acknowledged that the Omicron variant is more transmissible but less deadly, according to state news agency Xinhua.

Sun said the country is "facing a new situation and new tasks as the pathogenicity of the Omicron virus diminishes, vaccination becomes more widespread and experience in prevention and controls".

It is the first time a senior official has acknowledged the change in the nature of the virus without the usual caveat that Omicron could still lead to more deaths in China because of its large population an argument that has previously been used to justify the country's strong Covid-19 controls, Hong Kong-based South China Morning Post reported.

Meanwhile, security has been beefed up in Beijing, Shanghai and several other cities which witnessed anti-zero covid measures rattling the government as it prepared for next Tuesday's funeral of former Chinese President Jiang who died on Wednesday.

Deaths of top Chinese leaders including former premier Zhou Enlai and former General Secretary of the ruling Communist Party of China (CPC) Hu Yaobang followed mass protests in Tiananmen Square in Beijing.

While the military dispersed mass protests after Zhou died in 1976, hundreds of students were reported to have been killed in the 1989 Tiananmen Square protests demanding democracy and freedom of speech following the death of Hu, the Communist leader who pursued political and economic reforms.

There is a sense of disquiet in Beijing over the weekend anti-zero covid protests in which slogans calling for President Xi Jinping to step down were raised coinciding with the death of former president Jiang.