Indonesia is set to send 79 containers of hazardous materials back to Australia, New Zealand, the United Kingdom and the United States beginning in January, the government recently revealed.

The Foreign Ministry summoned the envoys of the four countries to notify them about the plan on Wednesday, according to the ministry's statement published on Thursday.

The ministry’s director general of American and European affairs, Ngurah Swajaya, said the measure was in accordance with international law, namely the Basel Convention on the Control of the Transboundary Movements of Hazardous Wastes and their Disposal.

The treaty was designed to reduce the movements of hazardous materials between nations, specifically to prevent the transfer of hazardous waste from developed to less developed countries.

"In accordance with the Basel Convention […], cross-country imports containing toxic waste are not allowed. The Indonesian government must return it to the origin country," he told the ambassadors.

Read also: Toxic waste smuggling at Indonesian ports takes toll on local plastics industry

Ngurah said the containers had been verified by various government agencies including the Environment and Forestry Ministry, Trade Ministry, Industry Ministry, Finance Ministry and the National Police.

"The 79 containers to be re-exported are part of the total 107 containers that had been confiscated by the Indonesian government because they contained hazardous waste, while the remaining 28 containers will be re-examined," he added.

The containers were confiscated in 2019, during which Indonesia, together with other Southeast Asian nations faced a sharp increase in shipments of plastic waste from developed countries to developing nations following China’s decision to ban imports of 24 types of waste materials.

Nonhazardous waste, mostly consisting of clean scrap paper, was intended to be used by paper-recycling companies in Indonesia. However, most of the cargo was found to be contaminated by hazardous waste such as old diapers and plastics, which the businesses reject and ends up in landfills.