Thailand has added more measures to arrest its biggest coronavirus outbreak yet, including a nationwide requirement to wear masks in public and a ban on dining at restaurants in and around its capital.

Authorities reclassified Bangkok and five provinces as the highest-controlled zones. There are 46 others with broad restrictions after a third Covid-19 wave that has seen more than half of the country's overall infections this month alone.

Parks, gyms, cinemas, bars, restaurants, day-care centres and schools have been closed in Bangkok, the outbreak epicentre, and non-essential travel from the capital is being discouraged.

“This is not a lockdown, not a curfew, but we are asking for your cooperation,” coronavirus taskforce spokesman, Taweesin Wisanuyothin said, according to Reuters.