Tin production in Indonesia, the world's largest exporter, will fall by up to a third this year due to new government regulations to clean up the industry, the head of the country's largest manufacturer predicted yesterday.

Thobrani Alwi, the president of Timah, estimated that production would drop to 80,000-90,000 tonnes from 120,000 tonnes last year because the rules will force the majority of exporters out of business for months and some permanently.