Indonesia will ratify a Southeast Asian agreement that calls for regional cooperation to deal with forest fires blanketing the region with choking smog, a presidential spokesman said on Thursday.

The pledge came a day before environment ministers from five Southeast Asian nations are due to meet in Pekanbaru on Indonesia's Sumatra island to discuss ways to tackle the problem.

Jakarta has been criticized by its neighbors for failing to tackle the annual dry season blazes, which in past weeks have caused serious air pollution across the region, particularly Malaysia and Singapore.

The Association of South East Asian Nations approved the ASEAN Agreement on Transboundary Haze Pollution in 2002, but Indonesia's parliament has yet to ratify it, angering countries affected by the smoke, known as haze in the region.

"Indonesia will ratify it and at the same time adopt a comprehensive solution to the haze problem," said Dino Patti Djalal, a spokesman for President Susilo Bambang Yudhoyono.

Fires caused by farmers and big businesses such as plantations have been burning for weeks in parts of Indonesia, creating a choking haze that has made many people ill, shut some airports and threatened wildlife in protected forests.

Djalal said Yudhoyono had telephoned Singapore Prime Minister Lee Hsien Loong to discuss the forest fires and explain to Lee the problems Jakarta faced in trying to extinguish the blazes.

"The president stressed the need for a comprehensive long-term solution. The president also pins high hopes on the environment ministers' meeting on Friday," he said.

The meeting in Pekanbaru, itself regularly affected by the haze, is expected to be attended by ministers from Indonesia, Thailand, Malaysia, Brunei and Singapore.

Yudhoyono on Wednesday apologized to neighboring countries.

Most of the blazes are in southern Sumatra, just across the Malacca Strait from Malaysia and Singapore, as well as in Indonesia's part of Borneo island.

Yudhoyono said Indonesia would use all resources available to put out the fires, including enlisting soldiers and police and leasing two Russian cargo aircraft that could each carry 40 tonnes of water to douse fires.

Malaysia would ask at the meeting of environment ministers for a special fund to be set up to tackle the haze, state news agency Bernama reported.

"The important thing is for these countries which are receiving the impact of the haze to agree to collaborate and take positive and effective action to ensure that it does not recur," Deputy Prime Minister Najib Razak was quoted telling reporters at a Malaysian Armed Forces function.

Environment Minister Azmi Khalid said countries affected by the haze or causing the haze should contribute to the fund, Bernama said.

With few signs authorities have a grip on the situation, residents have been forced to pray for rain.

Severe fires and smog during a drought in 1997-98 made many people ill across a wide area of Southeast Asia and cost local economies billions of dollars and badly hit the tourism and airline sectors. The this year's haze has rekindled fears over the economic and health impacts to local economies.

Indonesia bans slash-and-burn practices by farmers, timber firms and plantations. But prosecutions take time and few have stuck.