--PT Bumi Resources receives South Jakarta court approval to set up audit team.

--The team will conclude audit within 90 days of the appointment of auditor.

--Court approval paves way for PT Bumi and Bumi PLC cooperation, person familiar with decision says

--Move comes after alleged financial irregularities in PT Bumi.

(Updates with background.)

By Andreas Ismar and Eric Bellman

JAKARTA--Indonesia's biggest thermal coal producer, PT Bumi Resources (BUMI.JK), has received a court approval to set up an audit team, it said in a filing to Indonesian Stock Exchange Friday, adding that the team is expected to conclude and send its report to the court within 90 days after appointing the auditor.

"The South Jakarta district court on November 8 has approved request lodged by our audit committee" to conduct a thorough audit, it said in the statement, adding that it made such request to the court on Oct. 15. The company didn't say when it will appoint an auditor.

The court ordered the company's "president director, board of directors, and employees to provide all data and information required for audit", in particular information related to financial management, investment and other transactions between 2010 and the first half of 2012, the company said, adding that it will also audit its January-September financial reports, which will be published by Dec. 31.

The move came after its major shareholder, London-listed Bumi PLC (VLLRF, BUMI.LN), in September launched an investigation for alleged financial irregularities involving more than $500 millions in its Indonesian subsidiaries. Bumi PLC, which appointed U.K. law firm Macfarlanes to carry out the probe, owns a stake of just over 29% in the Jakarta-listed Bumi Resources.

The Indonesian court decision was necessary to allow Bumi Resources to cooperate with Bumi PLC's investigation, a person familiar with Bumi Resources thinking said.

"With this initiative, the company reaffirm its commitment towards law enforcement in Indonesia...We believe that these proactive steps were taken in order to protect stakeholders interests and also to fairly address" concerns raised by Bumi PLC, Dileep Srivastava, corporate secretary of Bumi Resources, said in the statement.

Indonesia's Bakrie Group, which helped create Bumi PLC last year when it folded its mining assets into a shell company created by financier Nat Rothschild, last month offered $1.2 billion to buy back its assets and pull out of the venture after several public spates with Mr. Rotschild.

The proposal put forth by Long Haul Holdings, a unit of the Bakrie Group, involves three deals. First, PT Bakrie & Brothers (BNBR.JK) and Long Haul will cancel their 23.8% stake in Bumi PLC in exchange for the equivalent value in Bumi Resources, or a 10.3% stake. Secondly, the Bakrie Group plans to buy Bumi PLC's remaining 18.9% stake in the Indonesian unit before the end of the year.

And thirdly, the Bakrie Group wants to buy Bumi PLC's other big coal asset, PT Berau Coal Energy (BRAU.JK). Bumi PLC owns an 85% stake in Berau, fifth largest coal mining company in Indonesia.

Should Bumi PLC's board approved the $1.2 billion proposal made by Bakrie Group, it would leave the London company as a cash shell. Nat Rotschild earlier this week had submitted an alternative proposal to Bumi PLC, which details are still unclear. One thing is certain, though: Bumi PLC said that it would only make recommendations on incoming proposals once the investigation has been completed.

Write to Andreas Ismar at andreasismar.sandiwan@dowjones.com and Eric Bellman at Eric.Bellman@wsj.com

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