The Maori Party won't say whether the welfare proposals put up by the National Party would be a deal-breaker in coalition negotiations after the election.
The leaders of the Maori, Mana and Green parties and United Future debated election issues on Radio New Zealand's Morning Report programme on Wednesday.
If re-elected, National wants single parents with children five years and older to take a part-time work test and be available for full-time work once their youngest child turns 14.
It would also expect those who have another child while on welfare to be available to work again after one year - which Maori Party co-leader Pita Sharples says his party does not support.
"There's no doubt that there is a punitive aspect to this whole thing," he said.
For the past three years, the Maori Party has had a confidence and supply agreement with the National-led Government.
Dr Sharples told the programme that parties going into coalition seek opportunities for their stand and the people they represent.
"At the end of the day it's sitting down at the table and weighing things up. Then we go back to our people and say, do you want to go in or not?"
United Future leader Peter Dunne also said the plan for a single parent beneficiary to be available for part-time work a year after having another child was going too far.
He said the time for people in that situation to start moving back into the workforce is when children are school age.
Mana Party leader Hone Harawira said he sees no reason to compromise on welfare policy.
Mr Harawira said National has taxed the poor to give more money to the rich during the past three years, and no welfare policy from National has ever helped get the poor off the bottom of the heap.
And, in a thinly-veiled criticism of his former colleagues in the Maori Party, he said that "simply being in bed doesn't mean that you actually advance anything."
"You might get a couple of things you can hang your hat on," he said, "but hanging your hat on a programme doesn't necessarily advantage the people that you are there to serve."
Mr Harawira said the Mana Party wants the state to provide breakfast and lunch for hungry children in decile one to five schools, at a cost of $38 million a year, which he says could be done by bringing back New Zealand Defence Force staff in Afghanistan which costs $40 million a year.
Green Party co-leader Metiria Turei told Morning Report that the current welfare system traps beneficiaries into low levels of training and poor, low-paid jobs.
She says the priority should be on education, to prepare people for a new wave of green jobs she says will be coming onstream.
Ms Turei says the Green Party's plan to create 100,000 new jobs comes partly from extending the home insulation scheme and investing in renewable energy technology.
The party is hoping it will have more than the present nine MPs in Parliament after this election, but Ms Turei says it's too soon to say if the Greens would enter a deal when the next Government is formed.