For many leaders, mounting public anger and a rapidly worsening economic outlook would be cause for worry and a policy rethink.

But Chinese President Xi Jinping, who doubtless would prefer smoother sailing in the run-up to a third leadership term, is doubling down on a signature "dynamic zero" COVID-19 policy that has been increasingly tested by the more infectious omicron variant.

Xi's high-profile reiteration of the policy, made last week during a visit to the southern island of Hainan that capped days of state-media support for it, reflects a political imperative not to reverse course and look weak in a year in which he needs to appear strong, analysts said.