Foodstuffs has argued a merger blocked by the Commerce Commission would benefit consumers and suppliers. 

The competition watchdog has decided merging the chain's North and South Island co-ops would substantially lessen competition. 

Foodstuffs North Island CEO Chris Quin says they're likely to appeal the decision - based on the evidence they have at this point.

He says the move would only have changed the support each retailer received. 

"Which is out of sight of customers and a part of retail competition - to bring it together in a more efficient way so that we can keep delivering value and innovation for New Zealanders. That's the disappointing thing about today's outcome." 

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