An online supermarket says removing GST from fruit and vegetables wouldn't be reflected at the checkout.
National says Labour is poised to announce that as policy, and it's been leaked the information.
The Prime Minister and his MP's will neither confirm nor deny the idea.
Supie Founder Sarah Balle told Heather du Plessis-Allan that if it were to go ahead, consumers would see a one-time sugar hit.
She says then the normal market pricing mechanisms of supply and demand would kick back, and then those involved would look to cover the costs of the extra administration.
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