Jakarta. The Indonesian Ulema Council (MUI), the country's top Islamic clerical body, has issued a fatwa declaring it haram, or religiously forbidden, to dispose of waste in rivers, lakes, and the sea, citing mounting environmental damage and public health risks.

The ruling was announced on Sunday during a river clean-up and tree-planting event in Sentul, West Java, held to mark National Waste Awareness Day and ahead of the holy month of Ramadan.

MUI Deputy Secretary General for Economic Affairs Hazuarli Halim said the decision followed extensive deliberations on the increasingly visible impact of environmental degradation.

“The fatwa prohibiting indiscriminate waste disposal is the result of serious consideration. Environmental pollution harms life and public health, and that is why we have declared this practice haram,” Hazuarli said.

He explained that from an Islamic perspective, protecting the environment is a moral obligation that brings spiritual merit, while polluting it constitutes a sin.

“Preserving the environment is a duty and earns reward. On the other hand, damaging it is haram and sinful. If state law carries criminal penalties, religion carries moral consequences,” he said.

MUI plans to widely disseminate the ruling through mosque networks and religious preachers across Indonesia. According to data from the Religious Affairs Ministry, the country has around 800,000 mosques that could serve as hubs for environmental education.

“If these 800,000 mosques actively promote environmental literacy, public awareness will grow. Sermons and religious lectures must include messages about protecting nature,” Hazuarli said.