Garner, who was expected to leave HSBC early in 2013, joined the bank in 2004 and has been responsible for its retail and commercial banking business in Britain since December 2010.

Garner said in an internal note to staff on Thursday he "had no desire" to join a competitor, an HSBC spokesman told Reuters.

His exit comes at a time of big upheaval for Britain's finance industry, as the government presses ahead with reforms to split retail and investment banking operations and with banks' culture and pay practices coming under closer scrutiny.

Simoes, who joined HSBC in 2007 from consultancy McKinsey & Co and had a spell with the bank in Hong Kong, will take on Garner's roles and keep his European post. He had been running retail banking and wealth management in Europe since the start this year, and is also a director of HSBC Bank.

Garner also sat on the Financial Services Practitioner Panel, an industry group charged with challenging and working with industry watchdog the Financial Services Authority.

Along with other British banks, HSBC has also been caught up in scandals around the mis-selling of payment protection insurance and interest rate swaps in Britain.

(Reporting by Sarah White; Editing by Dan Lalor)

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