A group of more than 30 construction, architecture and tourism groups say they will be releasing in December cost and design details for a replacement for Auckland's ageing Harbour Bridge.
The Transport Agency rejected the option of a second bridge last year in favour of a $4.1 billion series of undersea tunnels.
However the ANZAC Centenary Bridge Group is undeterred and says a new bridge would be much cheaper to build and maintain.
The group's spokesperson, Richard Simpson, says initial projections suggest the bridge would cost between $2bn and $3bn.
He says the cost of bridge maintainence is between one-third and one-fifth of the cost for tunnels.