HSBC boss Stuart Gulliver has admitted in a memo to the bank's staff that it failed to live up to expectations, after it was accused of helping thousands of customers of its Swiss private banking arm to evade tax.
Reuters reported today that the memo also indicated he had been called to give evidence to "lawmakers". Chairman Douglas Flint has already confirmed his appearance before the Treasury Select Committee on 25 February.
However, in his note Gulliver pointed to efforts made to change how the bank works.
I share your frustration that the media focus on historical events makes it harder for people to see the efforts we have made to put things right.
But we must acknowledge we sometimes failed to live up to the standards the societies we serve rightly expected from us.
The memo came after thousands of pages of data were leaked by an engineer working for HSBC in Geneva. The row has also taken in senior executives at HM Revenue and Customs (HMRC), who were grilled by the Public Accounts Committee on Wednesday. Financial Conduct Authority chairman Martin Wheatley was also subjected to questioning.
Conservative party treasurer Lord Fink came under fire from Ed Miliband during Prime Ministers' Questions. Although Fink initially said he would sue Miliband for slander, he later told the Evening Standard he had engaged in "vanilla" tax avoidance, adding "everyone does tax avoidance at some level".
Earlier this week HSBC said it had overhauled its structure since 2011, clamping down on tax practices. It added that the client base of its Swiss private bank had fallen by 70 per cent since 2007.