In order to keep its position as the leading supplier of copper in the world, Codelco copper mine which is based in Chile has proposed an acquisition of a share of Teck Resources Ltd’s mine for US$500 million.

The sale would lessen the amount of new capital required from public funds while also aiding in Enami's debt reduction following years of losses from processing minerals for small copper mines in Chile.

Codelco hoped that the share would support the company's output, which fell to a 25-year low last year. That could be sufficient to stop BHP Group from becoming the largest copper business in the world, surpassing Codelco copper mine.

However, the mining society Sonami, which has a seat on the ten-person Enami board, would fight to prevent the transaction from being approved. Any transaction should go via an open and competitive procedure, according to Sonami. Teck owns 60% of Quebrada Blanca while Sumitomo owns the remaining 30%. Enami does not need to use its 10% carried interest to pay for capital expenditures.

The Sonami group intends to keep Codelco from acquiring control of the Chilean copper mines, which could pose a challenge to the deal's confirmation.