Royal Bank of Scotland needs to change its behaviour "at every level" to restore trust, its new boss has said.

Ross McEwan joined RBS in 2012 and took over as chief executive in October with the task of reviving the bank and its reputation after its £45 billion bailout by the British taxpayer and scandals such as the mis-selling of loan insurance.

"To move from stability to renewal, we need to first address and then clean up every aspect of how we treat customers," Mr McEwan said. "We need to change our behaviour at every level to reflect this simple truth."

New Zealander McEwan said feedback from staff, the public and customers had been "both sobering and illuminating".

"It has shown me the depth of feeling toward the bank, and the scale of the changes needed to rebuild trust. It has underlined just how hard the road will be to recovery."

RBS last month said it would take a £3.1bn hit to cover the cost of more past misdeeds, which is expected to leave it with a 2013 loss of up to £8bn pounds, further evidence of the scale of the challenge McEwan faces as he tries to revive the bank and allow the government to start selling its 81% stake.

McEwan, who is due to unveil his strategic plan alongside annual results on February 27, said: "My strategy for the bank, which I will spell out in detail, will start to address the complexities and operational issues of a bank this size. But the customer will be at its core."

McEwan said he planned to reward customers for loyalty and rid the bank of the bureaucracy that held up business growth.