National is defending a new $212 million road transport package, saying the party is not trying to buy votes in the regions.
Prime Minister John Key announced plans to use cash from the sale of state-owned assets to upgrade 14 roads across the country.
Two of the projects would benefit Labour-held electorates - Palmerston North and West Coast Tasman - which National are targeting. But a number also fall in safe National seats, such as Taranaki and Clutha-Southland.
"Team Key has always been very focused on roads," Key said, referencing National's new social media strategy.
"I think voters in any part of the country are going to assess what are the right suite of policies that any particular government that would be formed will bring to the table...we'll also be campaigning on lots of infrastructure initiatives. This is just a part of it."
He added: "What it recognises I think is that across roading projects in New Zealand we have spent a lot of money in the main cities... It does recognise across the regions that we do need a stronger infrastructure."
The new upgrades are "critically important" and will be welcomed by both locals and tourists. "They are costing lives," he said.
Transport minister Gerry Brownlee is proposing a further $90 million a year be spent on roads, over and above maintenance.
"When you put a camera in front of a politician and say you are buying votes I think we are going into an election where you lay out policy and people make a choice about it," he said.
"For the first time, we've had money available. It's come from the asset sales programme and we are honouring a commitment to spend that money on new assets for New Zealand... what we are going to do is give the regions roads an opportunity that they have wanted for a very long time."
Labour leader David Cunliffe called the roading announcement was an election year u-turn.
"After six years in office and three months out from the election, the Government has suddenly decided to return some of the road funding it took from the regions to pay for its $12 billion 'roads of national significance'.
"Labour has made it clear that this funding needed to be restored, but I think most New Zealanders will be wondering why the Government hasn't come up with a decent plan to create real wealth and grow jobs in the regions."
Cunliffe said Labour's plan for the regions was to support business and exporters to create well paid and secure jobs.
"Our Economic Upgrade will focus on investment, innovation and industry to create those jobs. We have already announced comprehensive plans to boost manufacturing and the wood sector in the regions. Our immigration policy, announced yesterday, also directs immigration towards boosting regional development."
Green party co-leader Russel Norman said the policy launch was "classic pork barrelling".
"This Government is using John Key's asset sales slush fund to pay for an election bribe for the regions," he said.
"National has been underfunding local roading in favour of a handful of uneconomic highway projects, leaving local councils to take on more debt to try and deal with the problem... much needed investment in local roads ...should have been a priority from the start."
THE NEW PROJECTS
•Whirokino Trestle Bridge replacement, Manawatu/Whanganui
•Motu Bridge replacement, Gisborne
•Opawa and Wairau bridge replacements, Marlborough
•Taramakau rod/rail bridge on the West Coast
•Safety improvements on the loop road north to Smeatons Hill, Northland
•Mt Messenger and Awakino Gorge Corridor, Tarananki
•Kawarau Falls Bridge, Otago
•Mingha Bluff to Rough Creek realignment, Canterbury
•Akerama Curves realignment and passing lane, Northland
•State Highway 35 slow vehicle bays, Gisborne
•Normanby overbridge realignment, Taranaki
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