Nisa has lost its chairman and two non-executive directors.

Chairman Mark Pullen and non-executive directors John Cleland and Shena Winning stepped down from the board at a nominations committee meeting held last week.

Although Nisa chief executive Neil Turton would not give details on the reasons for each of the departures, he said the trio had had “different views on the future strategy of the business”. But he insisted there had been “no bust-up” at the retail buying group.

Pullen joined Nisa as a non-executive director in November 2007 and was appointed chairman in May 2008. He has more than 30 years’ experience in the industry and was group finance director at Geest for 10 years.

Cleland has worked at Sainsbury’s, Asda, B&Q, Somerfield, The Co-operative Group and Esporta Health & Fitness. He was appointed chief executive of electronics retailer Maplin in March. He had been a non-executive director at Nisa since May 2011.

Winning joined Nisa as a non-exec in January 2010 and is a former finance director of Carpetright.

“Nisa is in a strong position, having recently announced growth for the half-year trading period, and the remaining board and members of Nisa thank Mark, Shena and John for their hard work and dedication over the years,” said Turton. “We wish them all the best in their future endeavours.”

Turton added that Nisa was now on the hunt for replacements for the departed three.

Stephen Jempson, joint owner of Sussex-based independent retailer and Nisa member Jempson’s and also deputy chairman of Nisa, will act as chairman until a replacement is found.

Earlier this month, Nisa reported a 0.9% increase in half-year sales to £771m. By volume, they rose 1.7% to 55.5 million cases.