Sir Sandy Crombie, the retiring chief executive of Standard Life and a director of RBS, says the Chancellor's plans to cap bonuses at the bank is "troubling".
Speaking to Scotland on Sunday, Crombie says the board has to act in the best interests of the company and warned the issue could still lead to resignations.
Crombie, who joined RBS in the summer as senior independent director, views the situation as a legal issue which the board cannot sidestep.
Legal action was taken by the RBS board after the Government said it may veto this year's bonuses amid the public backlash against excessive payments to bankers.
Crombie hands over his chief executive role at Standard Life to finance director David Nish next month.
He also dismissed continuing reports of a rift between himself and the company's former UK life and pensions boss Trevor Matthews who left to take over as chief executive at Friends Provident.
"There was no falling out. Trevor had ambitions for himself and his family and has pursued them. He has never said to me that he was frustrated over the succession issue," said Crombie.
Commenting on Sir Fred Goodwin's departure from RBS, he said the blame for any failings should be a shared one and not aimed at any individual.
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