THE UK's largest bank has announced a boardroom shake-up just weeks after its chief executive was forced to apologise over a tax avoidance scandal.

HSBC's head of remuneration and nomination committee Sir Simon Robertson will step down at the bank's annual general meeting next month, to be replaced by Sam Laidlaw, the former chief executive of British Gas owner Centrica, who has been on the HSBC board since 2008.

Meanwhile Rachel Lomax, a former deputy governor of the Bank of England who has also sat on the HSBC board since 2008, will become a senior independent director and member of the nomination committee.

The changes follow chief executive Stuart Gulliver's apology for 'unacceptable'' tax-avoidance activities linked to the bank's Swiss arm in the mid-2000s.

The bank has faced a political storm in recent weeks after a leak accused HSBC of helping around 30,000 account holders hide almost £78 billion of assets from tax authorities in their home countries.

Last month it was revealed that Mr Gulliver, who was not in charge at the time of allegations, received pay and bonuses of £7.6 million.

The bank's Glasgow-born chairman, Douglas Flint, also received a £2.5m pay package.

News of the board shake-up came as investors and analysts warned HSBC, as well as Standard Chartered, could be tempted to abandon their London headquarters to avoid a jump in the UK bank tax set to cost them a combined $2 billion a year

"I think it is a live issue for both names and that's the first time I've ever been of that opinion," said one HSBC shareholder, who also owns some Standard Chartered stock.

"It's always been talked about but there is a confluence of events for these stocks that now make it a realistic prospect."

HSBC could pay $1.5 billion under the levy this year, up from $1.1 billion last year, while Standard Chartered faces paying $500 million.

Gary Greenwood, analyst at Shore Capital, said Standard Chartered would be more likely to move than HSBC.

He said: "It moves the dial a little more in the direction of reasons to not be here rather than being here."