High street bellwether Marks & Spencer has launched the search for a new chairman after Robert Swannell announced plans to retire after six years in the role.

Mr Swannell aims to retire in 2017, but will stay on until his successor is appointed.

He said it was the "right time" for a new chairman to lead the board.

He said: "A year ago we chose Steve Rowe as our chief executive. Steve completed a thorough analysis of the business and developed a detailed plan to build a simpler and more relevant M&S.

"This plan is now under way and I feel that it is the right time for the business to look for a new chairman."

He added: "It is a real privilege to chair this iconic company and I will continue to do so until my successor is in place."

Senior independent director Vindi Banga will lead the hunt for a new chairman.

Mr Swannell became chairman of the retail giant in January 2011, taking over from Lord Rose.

A former investment banker of more than 30 years, Mr Swannell joined previous chief executive Marc Bolland at the helm during a difficult time for the chain as it sought to halt falling sales.

He leaves as current boss Mr Rowe continues the fight to turn around under-pressure sales in its clothing arm, with a wide-ranging overhaul that will see it shut stores and revamp its product ranges and prices.

M&S said last month that it will close around 60 clothing and home stores to focus on food, and warned of more than 2,100 job losses under plans to axe 53 overseas shops.

The UK closures will affect around 100 stores as it looks to cut back on clothing and home while boosting its Simply Food chain.

Details of the restructure came as it revealed an 18.6% fall in underlying pre-tax profits to £231.3 million for the six months to October 1, while bottom-line profits crashed 88.4% to £25.1 million.

Mr Swannell was also previously chairman of music retailer HMV Group until March 2011 and remains chairman of UK Government Investments, which includes UK Financial Investments - the body tasked with managing taxpayer stakes in bailed out banks.