As raging fires in the forests of Sumatra and Borneo fuelled fears that Southeast Asia would again be hit by haze, Malaysia's cabinet has refused to publish official pollution data.
Ministers fear the effect on tourism - in 1997, the numbers fell by 13 per cent to 6.2 million, compared with 7.1 million in 1996.
Haze on Sumatra has disrupted air traffic and prompted health warnings. Smoke slowed shipping through the Malacca Straits, and blanketed Kuala Lumpur in a mild haze. In contrast, Singapore's state-owned radio and television stations continue to publish the index while the National University of Singapore makes remote sensing images of the pollution available through the internet.
Bill Watson, senior lecturer in social anthropology at the University of Kent, said: "This is consistent with Malaysia's attitude of playing down what is happening ... One reason is that they want to maintain a neighbourly attitude towards Indonesia. Another possibility is the heavy Malaysian investment in the oil palm plantations in Sumatra and Borneo that are the root cause of the problem." Dr Watson, who has an interest in the impact of the Green Revolution on the region, travels to Sumatra next week to continue research into the causes of the haze.
"Indonesian forestry specialists argue that, although there has been considerable expansion of plantation agriculture over the past 20 years, the amount of burning had not increased substantially between 1996 and 1997 -- the smoke was caused by climatic changes, which meant the winds were not blowing with the same force and from the same direction as they usually do.
"The 1997 problems were caused much more by freak winds ... This seems to be happening this year as well. It may be due to climatic conditions rather than increased burning."
Research with colleague Roy Ellen, funded by the European Commission through its Rainforest Peoples programme, blamed plantation owners' insatiable demands for the fires getting out of control rather than slash-and-burn cultivators.