Supermarket owners all over the country have raised concerns over National's election promise to split up Foodstuffs.

The party wants to create a third player by separating Pak'nSave from New World and Four Square, subject to Commerce Commission agreement.

New World owner-operator Eric Rush says he's been working in this business for 16 years and putting 'long, hard' hours in - and he's raised doubts over this campaign promise.

"That just goes to show that they have no understanding of actually how it works. We'll find a way if we have to, but it's not going to be the same."

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