Chinese President Xi Jinping has stressed the need to keep lockdowns and other strict anti-coronavirus measures in place despite mounting public frustration amid spreading infections.

Xi made an address before senior officials of the local government on the southern Chinese island of Hainan on Wednesday.

The state-run Xinhua news agency quoted Xi as saying prevention and control measures against the coronavirus should be implemented to minimize its economic and social impact.

He reportedly stressed that persistence is victory, and that it's necessary to overcome "inattention and war-weariness".

Meanwhile, officials in China's financial hub of Shanghai on Wednesday confirmed 27,719 new coronavirus infections, a record high for the second straight day. Most of the cases were without symptoms.

With lockdowns still in place in many parts of the city, residents have complained about short supplies of food and other daily necessities, as well as restricted access to hospitals.