New Zealand fares better than most OECD countries in terms of difference between regions and main centres, Economic Development Minister Steven Joyce says.
A Salvation Army report is warning disadvantages faced by those living in the regions are growing.
The Mixed Fortunes report said if those trends continued, there was a risk that two New Zealands could be created - Auckland and the rest.
It said there was a slight north-south divide, with the South Island generally faring better than the North.
But there was also a rural-urban divide in which cities were better shape than their countryside neighbours.
Areas most disadvantaged were Northland and Gisborne, whereas Otago and Canterbury ranked highly.
Campbell Roberts, from the Salvation Army's Social Policy and Parliamentary Unit, said he was concerned about the future of the regions if no action was taken now.
"The long-term result of that was to find quite significant areas of social dislocation and social harm into the future."
The research did not look at why there were regional differences, but Mr Roberts suspected the regions were suffering because politicians targeted policies at larger populations.
"The short-term nature of government does lead to these sorts of inequities.
"While we have a three-year Parliamentary term I think we're going to struggle with these sorts of things because politicians are often looking for quick results - results which are more spectacular, and of course they can go to those areas where they impact most population."
Mr Joyce disagreed that there was risk of two New Zealands and told Morning Report politicians did not take a short termist approach on a geography basis.
"We do know the challenges - the challenges in terms of Northland and Gisborne have been long term challenges and in our varying ways we're working to help solve those challenges." The solution lay in encouraging investment into these communities.
Mr Joyce said the majority of regions were doing very well.
"The South Island in particular is doing well. Auckland is actually in the middle of the pack in terms of economic performance since the global financial crisis. Parts of the North Island are doing well and parts a are struggling.
The report criticised the government's growth model, which it described as typically neo-liberal, saying it was not directed at addressing regional disparities.
Report author Alan Johnson said a long-term, cross-party agreement was needed.
"We need to think about a longer term plan and beyond the three-year electoral cycle.
"Have some goals that all parties can sign up to, that says we are concerned that all New Zealanders and all parts of New Zealand share in the prosperity rather than have it concentrated in one or two places."
He said there should also be a national plan focusing on the needs of an ageing population, and on the rural areas where climate change will have a major effect.
But Mr Joyce said there was no point in a cross-party accord as progress in the regions was determined by the level of investment.