Three independent people with knowledge of the talks said the group had been selected in the first round and was now likely to make a formal bid.
The bid will allow the group -- which has interests in sectors as varied as metals, telecom and financial services -- to conduct a detailed due diligence of the Sydney-based company, which is listed on the Australian Securities Exchange.
Close to 20 players -- including the Anil Dhirubhai Ambani Group and consortia of Korea Resources Corporation and Daewoo and China's Shenhua Energy and Yanzhou Coal -- are believed to be interested in the company.
Only half of them are likely to be selected for the formal bid-level discussions starting next month.
Most analysts are surprised at the move, as the Aditya Birla Group is yet to firm up its plan to re-enter the power sector.
But at a time when global coal prices are rising due to shortages, acquiring coal assets has become a strategic option for trading purposes as well.
Whitehaven mines metallurgical and high-grade thermal coal and sells to global steel, power and metallurgical industries.
Whitehaven had asked Goldman Sachs to run the sale process, which started in October last year.
The promoters, with related entities, hold 85 per cent in the company.
Whitehaven's market capitalisation is $3.2 billion.
However, it is not clear which arm of the Aditya Birla group will bid. Essel Mining & Industries, a closely-held group company that at times doubles up as a group holding company, has interests in iron ore mining and ferro alloys.
It is believed that coal from Whitehaven can also meet the requirements of group companies Hindalco and Ultratech Cement.
"The bid date is April 1. The group is formalising the plan. It is too early to say who will bid and how money
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