The Government will announce within days whether it will use a public-private partnership to build a $2 billion, 5km stretch of Auckland highway.
Ministers want to complete the Waterview Connection - part of a 48km-long Western Ring Route - by 2015.
In August a steering group advised the Government a public-private partnership (PPP) would give the greatest value for money.
At the time Finance Minister Michael Cullen said a PPP, which would mean tolls of about $2 a trip, was looking "pretty positive", but he and Transport Minister Annette King told the expert group to do some more work.
Launching Labour's transport policy today Ms King said an announcement on the future of the road was "only days away".
"I understand officials are very close to completing the extra work I asked them to do and I look forward to making an announcement as soon as possible."
The announcement could reignite the debate on tolling -- with both parties promising tolls on major new roads, where an alternative route exists, but at different levels.
Dr Cullen has said they would likely be capped at around $2 a trip but National's transport spokesman Maurice Williamson has twice suggested a higher figure.
In August he said National could toll drivers $5 a trip, which would amount to $50 a week for daily commuters.
Despite a reprimand from his leader John Key who said the figure was too high, he again floated the idea of a $3 a trip charge this month.
Mr Key said his comments were "premature" as National had not yet set any level of tolls.
Despite those reversals Ms King today used Labour's policy launch to attack National, which she said had a secret agenda involving "large-scale tolling".
She also criticised National's policy as "road-centric".
"They never talk about walking or cycling or public transport.
"They certainly never talk about moving freight in any way other than by road."
National has proposed spending an extra $3.7 billion on key infrastructure, including roads, over the next six years.
National is promising to add to that pot by more aggressively pursuing PPPs across a range of infrastructure initiatives.
Labour's election transport policy promises a continuation of its existing policies.
Ms King said the contrast between the two parties' records was stark with the Labour-led government roughly tripling the amount spent on transport infrastructure.
Labour's policy also included ample provision for cycling, biking, rail for passenger transport and freight and shipping.
