MARKS & Spencer boss Marc Bolland will quit in April, the firm said, as it revealed “disappointing” Christmas results.
Mr Bolland will resign after a six-year battle to turn around the high street giant.
He will be replaced by M&S veteran of 25 years Steve Rowe.
M&S said like-for-like sales in its general merchandise arm, which includes clothing, slumped by 5.8% in the 13 weeks to December 26.
It blamed unusually mild weather and poor stock availability as customers shunned heavy coats.
Mr Bolland said it had been “a huge honour to lead one of Britain’s most iconic companies”.
He added: “I am delighted to hand over to Steve Rowe as my successor. I have worked closely with Steve for six years and I am convinced that he will be a great leader for Marks & Spencer.”
M&S chairman Robert Swannell paid tribute to Mr Bolland’s achievements and insisted Mr Bolland was not under pressure to quit from shareholders or the board.
Succession planning had been in train “for years”, Mr Swannell said, adding that the process had been “rigorous”.
Mr Bolland, who took on the post of chief executive in early 2010, will retire at the end of the group’s financial year on April 2, but will remain on hand to help with the handover until the end of June.