Indonesia’s parliament voted yesterday to ratify a regional agreement on cross-border pollution — 12 years late.

The decision was driven by fires sweeping forests in the west, choking neighbouring Singapore with smog.

Singapore and Malaysia have responded furiously to Indonesian forest fires, which have worsened in recent years.

Singapore’s air pollution soared on Monday as Indonesia failed to control fires in Sumatra’s tropical forests.

The regional agreement obliges Indonesia to strengthen its policies on forest fires, actively participate in decision-making and dedicate more resources to the problem.

Indonesia signed the Association of Southeast Asian Nations (Asean) Agreement on Transboundary Haze Pollution 12 years ago and has been under pressure to ratify the document.

“Indonesia has already carried out operations for the prevention, mitigation of forest fires and haze … at the national level,” the parliament claimed.

“But, to handle cross-border pollution, Indonesia and other Asean nations recognise that prevention and mitigation need to be done together,” it acknowledged.

Singapore and Malaysia are smothered in haze from Indonesian forests every year and fires last year caused the region’s worst pollution crisis in a decade, renewing calls for action in Indonesia.

Many fires are deliberately lit to clear land for commercial plantations and the authorities have arrested people caught in the act.

Singapore passed a Bill last month giving the government powers to fine companies causing or contributing to haze up to $1.6 million (£1m).