In January, AustralianSuper said it would double its lithium exposure in the next five years.

Shareholders in both companies interviewed by Bloomberg said there was still likely to be some room for a sweetened offer before a May 22 cut-off.

The Indian mines ministry is also encouraging other state-owned companies to scout for critical minerals overseas.

The company is planning a three-year, A$210 million pilot project that would pump 330,000 metric tons of CO2 from a coal-fired power plant.

Anglo American stated that the new offer was "highly unattractive" for its shareholders.

The incident, the second of this kind this year, happened in an area with no people nearby and it is being investigated, Rio said.

Australia’s critical minerals industry is a major part of the government’s push to capitalize on the worldwide green energy revolution.

Anglo shareholders have been urging the company to explain how it would create more value than by just selling to the rival.