The bid may also be a tacit admission on BHP's part that buying copper assets is far easier than trying to find them and develop new mines.

BHP's $39 billion bid will be the elephant in the room at Anglo American's Tuesday annual general meeting.

Its Tenke Fungurume site added new mining capacity in March, lifting annual capacity to 450,000 tons of copper and 37,000 tons of cobalt.

BHP is considering making an improved offer, Reuters sources said during the weekend.

Vedanta is trying to raise about $1.4 billion in total for Konkola.

The biggest producers all want to increase copper output to take advantage of rising demand for electric vehicles, grid infrastructure and data centers.

BHP Group is considering making an improved offer for Anglo American after its $39 billion initial proposal was rejected.

The Kerkasha site holds four Italian gold mines dating from the 1890 to 1941 colonial period.