(Insider Stories) -  Indonesia's tycoon Samin Tan through PT Borneo Lumbung Energi & Metal (BORN.JK) has made cash offer to acquire the Bakrie Group's existing 23.8% effective interest in Bumi Plc (BUMIP.L), said the spokesman in statement. The proposed deal would increase Tan's existing holding in Bumi Plc to around 47 percent from about 30 percent.

"The discussions and negotiations are ongoing, we believe the offer is value accretive to Bumi plc and its shareholders. We intend to proceed with this offer from Borneo Lumbung Energi & Metal," Christopher K. Fong, Bakrie Group's Senior Vice President said in statement.

The new separation deal differs from one originally proposed last year. In that scenario, the Bakries had agreed to exchange cash and their shares in London-listed Bumi for the group's minority holding in Bumi Resources.

Selling its stake in Bumi Plc would leave the company with an 85 percent holding in PT Berau Coal Energy, Indonesia’s fifth-largest exporter of energy coal.

Meanwhile, Bumi Plc said in their statemenet, this transaction would be effected through the Bakrie Group acquiring for cash Bumi's 29.2% interest in Bumi Resources and the Bakrie Group selling their indirect interest in Bumi to an affiliate of Borneo Lumbung Energi & Metal. The arrangement that is now being finalised entails the Bakrie Group purchasing the company's interest in Bumi Resources for over US$500 million in cash.

Bumi said that independent shareholders would have to approve Samin Tan's acquisition of the Bakries' stake in Bumi Plc.

In other hand, Nathaniel Rothschild's NR Investments Ltd said in a statement has proposed that the Bakrie’s stake be offered to existing shareholders rather than sold to Tan who could then underwrite the offer and be free to buy any stock not taken up. The revised separation proposal deprives investors of upside “just when thermal coal fundamentals are starting to improve,” according to the statement.

Rothschild, who owns a 14.8 percent stake in Bumi Plc, criticized the latest proposal. He also asked Britain's Financial Conduct Authority (FCA) to investigate whether Indonesia-focused coal miner Bumi (BUMIP.L) made misleading statements to the market.

London-listed Bumi Plc was co-founded by financier Nat Rothschild and the influential Bakrie family. But Bumi Plc and the Bakries have been seeking to part ways after two years of boardroom battles and a probe into financial irregularities.

Trading in Bumi's shares has been suspended since April after irregularities found in the accounts of a key subsidiary forced it to delay its full-year results.