Nat Rothschild, Co-founder of Bumi stepped up the bitter battle for control of the Indonesia-focused miner, attacking both the board for its inaction and CEO Nick von Schirnding for "embellishing his CV."
"He is not at all qualified to be the CEO of a global mining company, not just because he tried to make himself more well-qualified by embellishing his CV last week. It's staggering that there are board members who for two years have been so vociferous in their objections to me, against me raising the subject of bad corporate governance at the company. This is the collective responsibility of the board and I seem to be the lone voice in trying to deal with the serious issues at hand," Rothschild told CNBC.
Rebutting the accusations, Nick von Schirndling placed the blame for the company's woes firmly at Rothschild's door. He insisted he had plenty of experience in mining, adding he had "no idea" why Rothschild accused him of embellishing his CV.
Von Schirndling told CNBC there was no personal acrimony between himself and Rothschild.
"I've had 25 years of financial and operating experience. This company is in a total mess and that mess was created when Nat Rothschild bought the structure to the London market. He gave control of the Plc to the Bakries and that was a flaw. We are trying to sort this out and removing the Bakries," von Schirnding told CNBC.
(Read more: Coal Miner Moves Towards Bakrie Divorce)
The split between the two shareholders, Nat Rothschild and the Bakrie family, have grown increasingly acrimonious after a series of high-profile disagreements at the London-listed miner since their union in 2010.
Bumi's share price has suffered from the ensuing fallout, plunging 25 percent in 2012 on news that there were "financial irregularities" at PT Bumi Resources, in which Bumi owns a 29 percent stake.
The company announced earlier this month that it lost $632 million in the nine-months to September 2012 on the back of substantial derivatives losses. Operating profit slumped 60 percent for the period to $312 million.
Rothschild's latest plan to revive the company includes a revamp of the board of directors and the removal of 12 out of 14 directors.
(Read more: Bakries May Scrap Bumi Exit Plan if Rothschild Returns)
Rothschild also attacked the appointment of Eko Budianto as chief executive at Berau Coal, a company that is majority-owned by Bumi. Rothschild claimed Budianto was "unfit and had a chequered reputation" adding he "had no mining experience whatsoever."
"You have to contrast Budianto with others…he has no operational mining experience whatsoever, he has worked with the Bakrie concert party for three years and his ties with the family go back ten years," Rothschild said.
A "concert party" refers to a group of shareholders that buys shares with the aim of influencing or taking control of a company.
Bumi said it will hold an extraordinary general meeting on February 21 to vote on Rothschild's proposals with the unanimous recommendation that all proposals are opposed.
Bumi's London-listed shares traded down 3.3 percent on Tuesday morning.
By CNBC's Shai Ahmed; Follow her on Twitter @shaicnbc