The rules are aimed at preventing local smelting companies from buying ore at price level that are too low.
A monthly metal benchmark price set by the ministry will be used as floor price for nickel ore transactions under the new rules, said Yunus Saefulhak, the ministry's Director of Minerals.
The ministry will allow for some buffer below the floor price, but it has not decided yet how far below the floor can the selling price go, he said.
"We are optimistic we will conclude it by the end of March," Saefulhak said. Previously, the ministry had targeted to issue the rules in January, as Indonesia, a major nickel ore exporter, stop outbound shipments of unprocessed nickel.
The country banned exports of nickel ore two years ahead of schedule as it aims to establish a fully integrated nickel industry at home by processing the ore into metals and chemical used in batteries for electric vehicles.
Miners have said that prices paid by local smelters were too low, below the ministry's benchmark price, which is also used by the government to calculate royalties that miners have to pay.
(Reporting by Wilda Asmarini; Writing by Fransiska Nangoy; Editing by Arun Koyyur)