Around 200 million doses of Covid-19 vaccine have been administered so far inside China, with an emphasis on front-line workers, university students and people living in border areas, health officials said.

China is ramping up vaccination efforts after a slow start that was due in part to the virtual elimination of domestic transmission of the coronavirus.

China has approved five domestically produced vaccines and exported millions of doses, although some scientists believe they provide less protection that those by Pfizer, Moderna and AstraZeneca.

The Chinese vaccines have an efficacy range of 50.7 per cent to 79.3pc, based on company data, lower than their foreign peers but still effective, according to AP.