JAKARTA (Agencies via Xinhua) -- The smog blanketing vast tracts of Southeast Asia could choke the region's tourism industry into the peak Christmas season, travel executives said yesterday.

They said Western tourists had begun cancelling visits to the region's pleasure spots and more cancellations were likely as graphic images of the bush fire-induced disaster were played on television screens across prime markets in Western Europe and the United States.

"We have cancellations today," said Frederik Kapitan, managing director of Nusa Ina Reizen, a Dutch company operating tours in Indonesia.

"We don't know when the haze will lift and until that time all the tours will be in flux," he told reporters on the sidelines of the annual Tourism Indonesia Mart and Expo here.

Thousands of firefighters are battling to control fires which have burned swathes of Indonesian forests for over two months, sending a blinding smog across large parts of Indonesia, Malaysia, Singapore, Brunei and the Philippines and as far north as the Thai resort of Phuket.

Besides the health risks, many flights have been cancelled or delayed because the smog has reduced visibility.

"It's really hit the fan," said Hugo-Ernst Stinnes, an executive for STR Distribution Promotion, a company which promotes Southeast Asian tourist destinations from Germany.

He said Germany's ARD television channel aired a special programme on the smog on Thursday evening, and he had been told by colleagues that the effects could be disastrous.