Marks & Spencer group chief financial officer Humphrey Singer is to leave the retailer less than two years into the role.

Marks & Spencer said that a search for his replacement has begun and he will remain in post until a leaving date is agreed and to ensure an orderly succession.

Singer’s exit comes as chief executive Steve Rowe battles to turn the business around.

It follows Marks & Spencer’s demotion from the blue chip FTSE 100 index and the creation of a joint venture with etailer Ocado, which will enable M&S to sell its food online for the first time. It is also the second senior departure from M&S, after that of clothing supremo Jill McDonald in July.

Marks & Spencer issued a statement on Saturday confirming that Singer would leave, following a Sky News story.

That report said that M&S chairman Archie Norman had been unimpressed by executives’ performance on a roadshow promoting the £600m rights issue to fund the Ocado deal.

Singer, who joined M&S from Dixons Carphone, said: “I feel privileged to be a part of the challenging but hugely rewarding turnaround at Marks & Spencer. It is a brilliant business and a much-loved brand for our colleagues and our customers.

“The transformation taking place is of a scale, depth and pace not seen before at the company. After 18 months of working with Steve to lead the transformation strategy and rebuild the finance function I have decided that now is the right time to move on.

“I will continue to give the business my all and work with Steve and the board to ensure we continue to make progress and that there is an orderly handover to my successor.”

Rowe said: “Humphrey has been a huge asset to the business. He has helped to establish the foundations of our transformation with a stronger balance sheet, robust financial controls and a much keener focus on reducing our cost base.

“In addition, he was a critical part of the team which guided Marks & Spencer through the deal to create our joint venture with Ocado and subsequent equity raise. I look forward to continuing to work with him as we search for his successor.”