Jerry Marwood, UK managing director of symbol group Spar, is understood to be stepping down from the business, Retail Week has learnt.
It is understood Marwood will leave in the next few weeks, and it is not clear if he has a role to go to.
Spar was set up in the UK in 1957 with five founding wholesale members. It is now made up of six wholesale members servicing more than 2,600 stores.
Marwood is credited with transforming Spar UK, the biggest brand in convenience retailing, from an old-fashioned operation into a modern retailer.
Spar reported a 3.1% rise in first quarter sales to the end of July boosted by an improved fresh food and wine offer and expansion in own-brand products.
Spar did not return calls at the time of writing.