The growing row over the promotion of Stuart Rose to executive chairman at UK retailer Marks & Spencer has taken a fresh twist, as a group of pension scheme investors has rejected the company's justification for the move and proposed compromise.

M&S wrote to its shareholders on April 3, explaining its rationale for appointing Rose executive chairman for a three-year term, in contravention of corporate governance best practice. Investors typically favour separation of the roles of chairman and chief executive in order to avoid concentrating power.