China has reported its highest COVID-19 infection figures in more than three months, with more than 2,400 registered cases in one day, the National Health Commission announced on Sunday.

This is the highest figure since May 12. A quarter of those infected were showing no symptoms, according to the health authority.

China is pursuing a strict zero-Covid policy, imposing sweeping lockdowns and mass testing on any outbreak.

The measures have kept the virus under control since the second half of 2020, allowing the country to recover quickly. But the strategy is being pushed to its limits by the highly infectious omicron variant.

Regular lockdowns are crippling the world's second-largest economy and have caused domestic tourism in particular to plummet.

Tens of thousands of tourists are stranded on the southern Chinese resort island of Hainan, which currently has the country's highest number of COVID infections after local authorities ordered a comprehensive lockdown.