Tony Shiret, the highly regarded analyst and vocal critic of Marks & Spencer under the leadership of Sir Stuart Rose, has left Credit Suisse after 18 years with the bank.

Shiret was made redundant last week as part of a programme of job cuts in Credit Suisse’s equities department.

One of the most well known and respected of analysts, Shiret was named second of individual non-food retail analysts in the Thomson Reuters Extel Survey, and third in Institutional Investor’s ranking.

One person who has worked with him in the past told the Financial Times: “He’s like the Godfather of the sector in terms of experience.”

British Retail Consortium director general Stephen Robertson said: “It seems extraordinary to lose someone of his stature and wisdom.”

Kingfisher group communications director Ian Harding said: “It is a great loss to the City. Tony is independent of mind, and reports without fear or favour.”

Shiret has been highly critical of Marks & Spencer under Rose’s leadership, but his stance softened when Marc Bolland took the reins, dropping his sell rating to neutral.

Shiret, who could not be reached by the Financial Times, is thought to be considering a variety of options.

Credit Suisse declined to comment.