The Commerce Commission is pushing out its timeline for approving the Foodstuffs merger, due to "unresolved issues".
It now expects to reach a decision in October.
The North and South Island co-operatives - which run the Pak'nSave, New World and Four Square supermarkets - sought clearance to merge last year.
Foodstuff's North Island Chief Executive Chris Quin told Heather du Plessis-Allan “We knew this could happen, but we remain committed that this is the right thing to do.”
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