National is promising a radical shake-up of roading priorities if it wins the election.

Leader Christopher Luxon said that the party will prioritise 13 roads of national significance, including the previously announced four-lane highways between Tauranga and Whangārei.

He reckons the projects can be fully funded without raising fuel excise taxes.

Labour has slammed the Nat's transport projects as "laughable at best".

Transport Minister David Parker says the costs are as woefully light, as is the explanation of how it would be funded.

Infrastructure NZ CEO Nick Leggett joined Kerre Woodham to discuss the policy and its viability.

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