Tonge joins at a difficult time for M&S, whose shares have fallen 35% over the last year.

After more than a decade of failed re-inventions, the 136-year old clothing and food retailer set out on its latest transformation plan shortly after retail veteran Archie Norman became chairman in 2017 to work alongside Chief Executive Steve Rowe, who has been with the firm for 30 years and became the boss in 2016.

The plan suffered a setback last month when M&S reported a disappointing Christmas trading update, hammering its share price.

The British retailer said Tonge would start in June, describing him as a "world-class" finance director. M&S said David Surdeau, currently interim CFO, would remain with the business to support Tonge as he moves into his new job.

Tonge has been Greencore's CFO since 2016 and prior to that was managing director of its grocery business. Before joining Greencore he worked for investment bank Goldman Sachs.

He will receive an annual salary of 600,000 pounds ($775,800) and will be eligible to participate in M&S's annual bonus scheme and performance share plan.

Last week the group said non-executive director Katie Bickerstaffe was shifting to an executive role as chief strategy and transformation director from April 27.

But it is still to name a start date for Richard Price, its new clothing boss who was recruited from Tesco in November.

Shares in M&S were down 1.3% at 1132 GMT, while shares in Greencore were down 0.3%.

(Reporting by James Davey and Paul Sandle; editing by Kate Holton and Jane Merriman)