UPDATE Worst Haze Yet Covers Phuket as Whole Region Goes Into Smoke

THE WORST haze seen this century covered the Thai holiday island of Phuket today but the national government has yet to ask its Asean neighbor, Indonesia, to end the burning that causes a health risk to the citizens of neighboring Asean countries.

BANGKOK: Malaysia has ordered all schools to close for two days as choking haze blanketing a large swathe of south-east Asia is on track to become the worst on record.

The fog-like grey smoke caused by slash and burn techniques used to clear Indonesian forests has for weeks caused health problems, flight delays and school closures in Singapore and parts of Indonesia and Malaysia.

Hundreds of thousands of people are suffering acute respiratory infections as the region has struggled to find an effective response to the problem.

Malaysia's deputy prime minister Ahmad Zahid Hamidi took a swipe at Indonesia as his country cancelled sporting events including a marathon for 30,000 runners and local soccer matches.

"We hope Indonesia's commitment is not only on paper or mere statements pleasant to ears, but through implementation which could end all haze problems," he said.

Singapore last weekend was forced to cancel a final of swimming's World Cup.

The haze has even reached the Philippines island of Cebu which has suffered a week of polluted skies.

Malaysia's education minister Mahdzir Khalid ordered his country's schools to close for two days on Sunday, saying the haze is beyond Malaysia's control.

"This issue has to be addressed wisely and quickly as it can do harm to our children," he said. "We cannot compromise with anything that may bring harm to children in our schools."

In Kuala Lumpur, pollutant monitoring stations registered "very unhealthy" or close to "hazardous" levels.

High levels were recorded across peninsular Malaysia and Borneo.

Similar crises have gripped the region each dry season for decades as palm oil plantation owners have set fires to clear forests to meet rising global demand for the oil used for cooking and in household products.

But scientists predict the current outbreak is on track to surpass 1997 levels when pollution soared to record highs in an environmental disaster that cost an estimated US$9 billion.

"If the forecasts for a longer dry season hold, this suggests 2015 will rank among the most severe events on record," said Robert Field, a Columbia University Scientist based at NASA's Goddard Institute for Space Studies.

The fires have raged despite Indonesia deploying more than 20,000 troops, police and other personnel to fight them through water bombing and chemically-induced rainfall.

Under criticism from its neighbors, Indonesia has investigated more than 200 companies and ordered four to suspend operations for allegedly causing fires on Sumatra and Kalimantan islands.

But weak enforcement in Indonesia is exacerbated by a lack of transparency about land ownership, making it harder to pinpoint and punish perpetrators, experts say.

Indonesia is the fifth largest emitter of greenhouse gases, mainly from deforestation.

The NASA-linked Global Fire Emissions Database has estimated this year's fires have released around 600 million tonnes of greenhouse gases.

In the Indonesian province of Riau alone officials say 44,000 people have suffered acute respiratory infections.