If New Zealand First ends up backing a Labour Government, they will have another party to contend with - the Greens. Labour would need both NZ First and the Greens to form a Government.
The Greens and NZ First haven't engaged in talks, and the two parties' ideologies and policies clash all over the place.
Here are 16 policies the Greens and NZ First disagree on:
1. Whānau Ora
Greens - Support and strengthen Whānau Ora.
NZ First - Abolish Whānau Ora.
2. Māori Seats
Greens - Entrench Māori Seats and oppose any referendum to remove them.
NZ First - Abolish Māori seats via a binding referendum.
3. Treaty settlements
Greens - Put an end to 'full and final' Treaty Settlements.
NZ First - Fully, fairly and finally complete the settlement of all outstanding claims.
4. Māori wards in local Government
Greens - Introduce Māori wards at local government level.
NZ First - Remove racial separatism from Local Government Act.
Greens - Wind up Crown Irrigation Ltd, and halt all new big irrigation projects.
NZ First - Support water-efficient irrigation and economically viable water-storage schemes.
6. Rail to the airport
Greens - Light rail to Auckland Airport.
NZ First - Heavy rail to Auckland Airport.
Greens - Phase out the Navy's frigates, and replace with multi-role peaceful vessels.
NZ First - Enhance offensive capabilities of the Navy.
Greens - No new coal mines, fracking or deep-sea oil/gas drilling and mining on conservation estate.
NZ First - Support the extractive industries while ensuring core conservation values are maintained.
9. Water tax
Greens - Nitrate levy for farmers.
NZ First - Reject the taxation of water.
Greens - Increase benefit payments by 20 percent and remove all sanctions and obligations for beneficiaries.
NZ First - Require greater scrutiny of the benefit system, adjustment benefits and abatement levels.
Greens - Legalise cannabis.
NZ First - Law change only via referendum.
Greens - Treat all migrants with respect, dignity and compassion.
NZ First - Substantially increase the minimum English requirement and reduce net migration to 10,000 a year.
13. Same-sex relationships
Greens - Support same-sex marriage and relationships and adoption.
NZ First - Protect our social fabric and traditional family values from temporarily empowered politicians.
14. Māori involvement in immigration policy
Greens - Māori have a say in developing New Zealand's immigration policy.
NZ First - No racial separatism.
Greens - Crackdown on gambling, including advertising of gambling and pokie machines.
NZ First - Defend the racing industry and lawful gambling proceeds against unreasonable attacks.
Greens - Introduce a top tax rate of 40 percent for all incomes over $150,000 and introduce a capital gains tax.
NZ First - No income tax increase and no capital gains tax.