Tourists wear masks in Chiang Mai province, Thailand, April 2, 2019.
Tourists wear masks in Chiang Mai province, Thailand, April 2, 2019.

Thailand is providing delegates to an Asian finance minister and central bank summit with face masks this week as smoggy air pollution hits alarming levels.

The air quality index (AQI) in Chiang Rai, where Thailand will host the Association of Southeast Asian Nations' (ASEAN) Finance Ministers and Central Bank Governors' meeting this week, reached levels considered unhealthy at 240 to 250, government data shows.

"Masks were prepared, but [we] have not seen anybody wearing them in the hotel", Nadhavudh Dhamasiri, a senior Finance Ministry official, told Reuters.

Some 300 officials are expected for the meeting, with some already arriving. There are no plans to change the meeting venue or schedules, officials said.

"We have not prepared special measures because the dust situation is improving and has not affected the meeting schedules," Nadhavudh added.

Thai Prime Minister Prayuth Chan-ocha traveled north to see the pollution for himself and ordered agencies to alleviate the problem within seven days, starting with 1,900 spots across nine provinces, including Chiang Rai.

The government has already given out nearly 2 million masks to residents in the area, he said.

"The smog problem in nine northern provinces is due to agriculture burning in forests, which happens every year," Sate Sampattagul, Head of the Climate Change Data Centre at Chiang Mai University, told Reuters.

The smog was worse this year because of a drought and more illegal burning, he added.