3 (1) Subject to subsection (2), the Commission and the Commodity Board are each authorized to regulate the marketing of milk in interprovincial trade and for such purposes may exercise all or any powers like the powers exercisable by them in relation to the marketing of milk locally within the Province of Ontario under the Act and the Plan, with respect to
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(2) The authority to regulate the marketing of milk in interprovincial trade does not include any power that is exercised by the Canadian Dairy Commission under the Canadian Dairy Commission Act in relation to the marketing of milk in interprovincial trade.