SINGAPORE - Indonesia's Sinar Mas Group, the Widjaja family's energy-to-banking conglomerate, is planning to list power assets in an initial public offering of up to US$800 million (S$1.13 billion) in Singapore, in what could be the country's biggest IPO in four years, according to the Wall Street Journal.

The group is planning to bundle the assets into a business trust and launch the IPO in the first half of 2017, said the Journal, quoting people familiar with the matter.

Sinar Mas is planning to raise between US$600 million and US$800 million from the sale and bankers have already begun sounding out investors, the Journal said in its report on Thursday (Nov 10).

At the top end, the IPO would be would be the biggest for Singapore since the May 2013 launch of Asia Pay Television Trust by cable-TV operator Taiwan Broadband Communications, which raised US$824 million, said the Journal.

It added that a final decision has not yet been reached on which of the conglomerate's assets will be included in the trust.

Sinar Mas's energy and infrastructure unit, PT Dian Swastatika Sentosa Tbk, has operations in power and steam generation, coal mining and chemical trading, among other activities., said the Journal.

The conglomerate's other businesses comprise pulp and paper, agribusiness and food, financial services, real-estate development and telecommunications.