The Environment Agency has launched an investigation after almost 90 containers of alleged illegal waste from the UK were intercepted by Indonesian authorities.
The UK watchdog will repatriate the 1,800-tonne cargo, described as scrap metal, amid concerns it was heavily contaminated with liquid and mixed waste.
The containers will be released by Indonesian authorities at the end of March and should reach the UK a month later.
Andy Higham, head of the EA’s national environmental crime team, said: “We are working closely with the Indonesian authorities to establish the facts of this case.
“Illegal waste exports risk harm to human health and the environment in the country of export. It also undermines law-abiding recycling businesses back home.
“There is a legitimate export market for recyclable material. However, we will take vigorous action where there is evidence of waste being exported illegally.”