Indonesia's ambitious biodiesel program will increase the risks of deforestation as more tropical forest could be cleared to grow palm oil, environmentalists have warned, urging policymakers to implement a long-term ban on new plantations.

The country — which is home to the world's third-largest tropical forests but is also its biggest producer of palm oil — has steadily increased the portion in its biodiesel mandate derived from palm oil since 2018 to boost demand.

Looking to also curb costly fuel imports and its own planet-heating emissions, the Southeast Asian country raised the "bio" content in its biodiesel to 30% in late 2019 from 20% the year before, with the rest being fossil fuel.