His departure follows the exit of two other directors a fortnight ago, when Gerard Gavan and Graham Clements left the business and their roles as operations director and logistics director respectively.
Under Stewart, Internaçionale weathered a tough retail climate and posted flat profits of £5m and a 5% rise in sales to £130.5m for the year to March 31 2007. However, it is unclear how the retailer has performed recently.
An industry source said: “I believe that the deal’s first year financial requirements were not hit in time.”
The MBO team was led by Stewart and included Gavan and Clements, plus finance director David Milton. It was backed by a private equity syndicate led by Penta Capital and Barclays Scottish Leveraged Finance in September last year.
Stewart, who at the time of the buyout had worked at Internaçionale for 11 years, took almost a 20% stake in the deal. Milton, Gavan and Clements, shared 25% of the equity.