Fires belch smog across Southeast Asia annually, but this year's are the worst since 2015
Fires belch smog across Southeast Asia annually, but this year's are the worst since 2015 AFP / Wahyudi

Malaysia said Thursday it will raise pressure on its Southeast Asian neighbours to find a solution to recurring outbreaks of smog-belching forest fires in Indonesia, as air quality plummeted and more schools closed.

Blazes to clear agricultural land in the archipelago are sending toxic haze across Southeast Asia, with Jakarta's efforts to fight them using water-bombing aircraft and thousands of security forces proving futile.

The Indonesian fires are an annual problem during the dry season, but this year's are the worst since 2015 and have added to concerns about wildfire outbreaks worldwide exacerbating global warming.

Nearly 2,500 schools were closed across Malaysia Thursday -- including almost 300 in the capital Kuala Lumpur -- as were hundreds on Indonesia's Sumatra island and the Indonesian part of Borneo, where the vast majority of fires are burning.

Satellite images released by NASA Earth Observatory show Borneo covered in a pall of smoke.

The island is divided between Indonesia, Malaysia and Brunei. Acrid smog has also clouded the skies of Singapore in recent days, raising fears it may affect this Sunday's Formula One race.

Officials from regional bloc the Association of Southeast Asian Nations (ASEAN) have long struggled to come up with fixes for the smog outbreaks, signing an agreement and holding regular meetings, but with little effect.

Malaysian Environment Minister Yeo Bee Yin signalled she would again pursue the diplomatic route in an effort to find a solution to a crisis that has been recurring every few years for more than two decades.

"I will have a conference call with the ASEAN secretary-general to express our views, and we hope there will be a more effective mechanism at the ASEAN level so that we can cooperate to seek a long-term solution to address this problem," she told reporters.

This week, Indonesia said it has arrested 230 people suspected of being involved in activities that led to out-of-control fires sweeping the country.

Shrouded skyscrapers

Air quality remained at "unhealthy" or "very unhealthy" levels on an official index in most of Malaysia Thursday, with the yellow-ish smog shrouding Kuala Lumpur so dense that the iconic Petronas Twin Towers and other skyscrapers were barely visible.

Indonesia and Malaysia have been carrying out "cloud-seeding", which involves using chemicals in a bid to induce rain, since the haze worsened.

AFP journalists on a Malaysian air force flight over the country Thursday watched as a liquid solution was sprayed from the aircraft's open door over clouds and the smog-shrouded landscape below.

Air quality was at unhealthy levels in Singapore, where the striking waterfront skyline has been obscured for days.

The organisers of Singapore's F1 night race say that they have a contingency plan to deal with the haze, but insist the event remains on track.

Spectators will be able to buy face masks to protect against the smog at the circuit and assistance will be provided for those who do not feel well, Singapore tourism board said.

Wildfire outbreaks from the Amazon to Australia have stoked concerns about the impact on global warming -- not only do the blazes release huge quantities of greenhouse gases, they also destroy forests which are natural buffers against climate change.

Singapore Environment Minister Masagos Zulkifli lamented the environmental damage caused by the Indonesian fires: "The amount of carbon emissions generated from the fires will present a major setback to the global fight against climate change."

Indonesia insists it is doing all it can to fight the fires, many of which burn underground in peatlands, but experts believe they will only be extinguished once the rainy season starts in October.