Shareholders in HSBC have called for the UK financial giant to speak out on a blistering attack of its investment bank by a group claiming to be made up of senior executives at the company.

A number of investors in the bank have expressed disquiet at its handling of the allegations after Financial News revealed last month that a set of employees claiming to comprise high-ranking members of HSBC's investment bank had severely criticised the division’s boss, Robin Phillips, demanding his removal and accusing him of presiding over a period of “persistent failure”.