Trucks in the open-pit mine of PT Freeport's Grasberg copper and gold mine in the eastern region of Papua, Indonesia, September 19, 2015. Antara Foto/Muhammad Adimaja

Freeport-McMoRan and other copper miners have halted Indonesian shipments of copper concentrates to abide by a government ban on exports of unprocessed metal ores that took effect on Thursday, a mining ministry official told Reuters.

“Yes, in accordance with the regulation,” said Coal and Minerals Director General Bambang Gatot, when asked if shipments of copper concentrates from Freeport and Medco Energi unit Amman Mineral Nusatenggara have stopped.

Freeport and Medco officials were not immediately available for comment.

The ban also covers shipments of lead, zinc, iron and manganese concentrates. Only shipments of fully processed metals were now allowed.

Government officials said earlier this week they would revise the ban to allow concentrate shipments to continue beyond Thursday’s deadline in certain cases. But those revisions have yet to be finalised.

Indonesia announced in 2014 a ban on ore shipments to push miners to build smelters to process ore locally, although it allowed some concentrate exports to continue amid protests from the industry. The full ban was to take effect on Thursday.

The halt in Indonesian copper exports is not expected to have an immediate impact on global copper prices due to China’s ample metal stockpiles ahead of the Chinese New Year at the end of January. It will take export delays of several weeks before prices find support, traders said.