HANOI (REUTERS) - Vietnam reported a record high in new coronavirus cases on Thursday (July 1) and prepared to conduct mass testing on half of the population of its biggest city as it tries to contain its biggest outbreak so far.

Most of the 713 new cases were in Ho Chi Minh City, the southern economic hub of nine million people, about half of whom the authorities are aiming to test before Tuesday next week.

The city plans to introduce home quarantine for suspected cases, which could be replicated nationwide, the health ministry said, a shift in strategy that until now has relied on centralised centres often run by the military.

Vietnam has so far reported only 17,576 cases of Covid-19 and 81 deaths, most of which occurred since late April.

Health Minister Nguyen Thanh Long said it was crucial to try to tackle the spread now, or risk economic damage.

"The outbreak will continue, with more cases found in the community, in industrial parks, in crowded areas, and could spread further into a larger outbreak," Mr Long said.

Vaccine supplies would increase from this month, he said, with about 30 million doses likely to arrive in the third quarter.

He said the government plans to vaccinate 70 to 75 per cent of the 98 million population by the end of this year or early next year. Around 200,000 people in Vietnam have so far been fully vaccinated.