China on Friday eased some of its Covid-19 restrictions, including shortening quarantines by two days for inbound travellers and close contacts of infected people and removing a penalty for airlines for bringing in too many cases.

The loosening of the rules came a day after the Politburo Standing Committee pledged to stick "unswervingly" to the zero-Covid policy. A notice from the country's disease control agency on Friday said the Politburo Standing Committee met on Thursday to approve the relaxations.

Under the new rules, centralised quarantine times for close contacts and travellers from abroad were shortened from seven days to five days.

The requirement for three further days in home isolation after centralised quarantine remains.

Inbound arrivals will still be required to undergo six nucleic acid tests and will not be allowed to freely set foot outside during those eight days.

The notice added that travellers will only be required to show one negative Covid test within 48 hours of boarding flights to China, a reduction from the current two tests.

Meanwhile, a so-called "circuit breaker" mechanism on inbound flights would be abolished, bringing an end to a policy that saw the closures of flight routes if a certain proportion of passengers tested positive for the virus.

Authorities will stop trying to identify "secondary" contacts -- those who may have come into contact with people who recently passed near infected people -- while still identifying close contacts.

Mainland authorities are also adjusting the categorisation of risk areas to simply "high" and "low" risk, eliminating the "medium" category, an effort to minimise the number of people coming under control measures.

"Optimising and adjusting prevention and control measures is not relaxing prevention and control, let alone opening up and 'laying flat', but to adapt to the new situation of epidemic prevention and control and the new characteristics of Covid-19 mutation," the National Health Commission said.

The commission also said it would develop a plan to accelerate vaccinations.

The easing of rules comes even as case numbers surge to their highest in months, with Beijing and the central city of Zhengzhou seeing record tallies. (Agencies)