The buyer is expected to be Andi Syamsuddin Arsyad, commonly known as Haji Isam, according to Forbes.

He is acquiring about half of Low's 62% stake in Bayan, as the Jakarta-listed coal miner declared force majeure this week on its coal supply contracts because the Indonesian government has yet to approve Bayan's revised mining quotas.

Indonesian billionaire Low Tuck Kwong, founder and president director of PT Bayan Resources. Photo courtesy of SEAX Global

Bayan, which operates the country's largest coal mine Tabang/Pakar, did not disclose financial details or a target completion date for the transaction. Arsyad has reportedly offered to buy Low's entire controlling interest in Bayan for $3 billion, valuing the company at just $4.8 billion, a fraction of its $22 billion market capitalization.

Arsyad, a known ally of Indonesia President Prabowo Subianto, has been seeking control of Bayan in a deal that would make him one of the world's top coal producers, according to The Business Times.

Tabang/Pakar, the largest coal mine in Indonesia, operated by Bayan Resources. Photo courtesy of the company

His PT Jhonlin Group is already a major coal producer and has sought a government quota to produce about 60 million tons of coal this year. The group also has interests in palm oil and logistics.

Singapore-born Low, who became an Indonesian citizen in 1992, is the richest in the country with $19 billion in net worth as of Sept. 18, according to Forbes's real-time data.