The spat between Nat Rothschild's NR Investments and resources firm Bumi has taken a new twist following allegations about its chief executive's qualifications.
Following a statement from Rothschild's NR about Nick von Schirnding, Bumi's board has hit back and said the financier's criticism amounts to nothing more than an attempt to take over the company.
'Nick is doing an outstandingly good job while putting up with these poorly judged attempts to tarnish his reputation as part of a campaign to take over the company.
'This is an extraordinary demonstration of a confrontational style which does not create value for shareholders,' said Sir Julian Horn-Smith, Bumi's senior independent director and chair of its nominations committee.
The fresh tussle comes after Rothschild increased his stake in Bumi ahead of a key investor vote.
Rothschild, who co-founded the firm roughly two years ago with Indonesia's Bakrie family, quit its board last year and since exiting has been vocal about the need for change.
He has asked Horn-Smith to up his response to allegations of financial irregularity at Bumi - urging him to quit his position without more than a placatory response to the claims - and has received backing for his turnaround plans from influential shareholder Richard Buxton, fund manager at Schroders.