Heavy smog blanketed the Thailand capital on Wednesday, forcing authorities to shut down more than 400 schools.
Air quality in Bangkok climbed to an "unhealthy" 170 on Tuesday morning.
"We cannot simply put the blame on people and penalise all the polluters because the outcome of penalty measures will create other serious problems for society," Prime Minister Prayuth Chan-ocha told reporters.
Some officials claimed it's a "cocktail of factors" with unregulated burning of sugarcane crops being the main polluter despite the ongoing two-month ban.


EU agrees to indefinitely freeze Russian assets, removing obstacle to Ukraine loan
Severe floods force mass evacuations in US state of Washington
At least 30 killed in Myanmar after junta airstrike hits hospital
Tsunami advisory lifted after earthquake hits Japan's northeast
Thai PM says he will speak to Trump late Friday on Cambodia clashes
