The Real Good Food Company had already indicacted that instability in the sugar market was causing it challenges.
One of its subsidiaries, Napier Brown, is involved in an ongoing pricing dispute with British Sugar, owned by Associated British Food.
Napier Brown has made a complaint to the Office of Fair Trading (OFT) that has now been referred to the new Competition and Markets Authority (CMA), which succeeds the OFT from April.
Yesterday, Real Good Food, which counts Carluke-based R&W Scott among its subsidiaries, said British Sugar temporarily withdrew sugar supplies to Napier Brown earlier this month.
It also admitted it was unlikely the dispute would be settled soon.
Real Good Food said the impact on Napier Brown and its Garrett Ingredients business would be "significant" and would be reflected in the full-year results for the 12 months to March 31, 2014, as well as the following financial year.
British Sugar said: "The recent commercial dispute between the two companies is not a matter upon which it is appropriate to comment."
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