Bloomberg quoted two people with knowledge of the transaction saying that the company is offering as much as $700m for the stake acquisition.
First Quantum already owns an 80% stake in the Kansanshi mine, which is located in Zambia’s North-Western Province.
The remaining interest is held by state-owned ZCCM Investments Holdings.
As part of the proposal submitted last year, First Quantum offered $300m to $400m in cash and an equal amount in special royalties for a period of more than ten years, sources said.
Zambia Finance Minister Margaret Mwanakatwe said at a mining conference: “There are multiple unsolicited offers on the table, including from FQM, which are based on preferential share conversions.”
Mwanakatwe said that the offers pertain to the 17% stake held by the ministry in ZCCM Investments and a sale would be subject to approval by the cabinet.
Kansanshi accounted for more than half the company’s revenue in 2017. It is said to be First Quantum’s biggest mine.
The mine began operations in 2005 and has undergone several expansions since then.
The initial production capacity of Kansanshi was 110,000t of copper. The mine is now capable of producing 340,000t of copper and more than 120,000oz of gold annually.
This week, First Quantum restarted copper production at its hydrometallurgical plant located at Cobre Las Cruces operation in Gerena, Seville Province, Spain.