Labour's calling for caution, while agreeing with National that Auckland needs a new harbour crossing. 

The Infrastructure Commission last week suggested a toll as high as $9 to fund the new crossing - and also tolling the existing bridge. 

But Chris Hipkins ruled out tolling Auckland Harbour Bridge at his State of the Nation speech yesterday. 

Newstalk ZB senior political correspondent Barry Soper explained why this position doesn't quite match Labour's earlier stance on extra costs for road users.

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