Thailand launched a mass Covid-19 vaccination drive on Monday as it seeks to beat a third wave of infections and reboot its vital tourism industry, which has been devastated by pandemic travel curbs.

The kingdom plans to give out some six million jabs in June, initially focusing on Bangkok -- where the country's current third wave began -- and the tourist island of Phuket.

The push comes as the government faces criticism over the slow pace of its vaccination strategy -- less than three million of the 70 million population have got a shot -- and concerns over supplies.

Shopping malls and supermarkets were among the 25 vaccination sites in action around the sprawling capital, which is aiming to inoculate up to 70,000 people a day, mostly with locally produced AstraZeneca shots.

Thailand managed to keep infections low through most of 2020 thanks to draconian travel restrictions and swift isolation for positive cases.

But an outbreak that began in a Bangkok nightlife district last month has seen overall cases rise sharply to nearly 180,000, with more than 1,200 deaths.

"They (the government) were caught off guards, couldn't prepare or come up with anything in time, and they were careless," 37-year-old Off told AFP after receiving his first jab at Bangkok's Siam Paragon mall.

Thailand's crucial tourism sector has been hammered by tight travel restrictions, including two weeks' hotel quarantine for all visitors, as tourist numbers have dwindled to a trickle.

Officials hope the vaccination drive will let them forge ahead with plans to ease travel curbs later in the year, starting with Phuket next month.

The aim is to jab 70 percent of the Phuket population and allow fully vaccinated tourists to stay on the island without going through quarantine.