An activist shareholder group said the potential addition of U.S. Steel's 11 blast furnaces to Nippon Steel's operations will almost certainly increase the company's cost of decarbonization.
The southern African nation, one of the top crude producers on the continent, has become a focus for the US in its campaign to secure critical minerals such as copper as it competes against China.
Efforts are part of India's membership under the US-led Minerals Security Partnership (MSP), which New Delhi joined last year to ensure critical minerals supply.