Hong Kong's health facilities have been overloaded by an “onslaught” of Covid-19 infections, its leader said, even as authorities cling to a “zero-Covid” policy despite an unprecedented rise in cases fuelled by the Omicron variant.

“The onslaught of the fifth wave of the epidemic has dealt a heavy blow to Hong Kong and overwhelmed the city's capacity of handling,” leader Carrie Lam said in a statement.

The surge in cases has increased wait times “for admitting people who test positive to isolation facilities,” she added.

Surrounded by patients queuing for tests all of last week, the city's hospitals told people who have “stable or have mild symptoms” to stay at home.