Green Party co-leader Metiria Turei will meet with Work and Income's investigative unit next week to calculate how much money she will pay back.

"I have been contacted and we are in the process of arranging a meeting for me to go and speak with them sometime next week.

"That will be the first proper conversation, and they will talk to me about what it is that they need. It may go on for some time, in terms of more appointments."

Turei said she didn't have a rough idea of how much she could owe. She had not taken legal advice before or after her admission, and had not considered how any possible investigation or charges would affect her Parliamentary career.

"Whatever the overpayment is, I've committed to paying it."

Labour leader Andrew Little would not rule out a Cabinet place for Turei if the two parties formed the next Government, but said he did not condone breaking the law.

In her speech at the Green Party's annual conference earlier this month Turei revealed that while at law school as a solo mother she deliberately didn't tell Work and Income how many flatmates were living with her because her benefit would be cut.

That situation occurred in three different flats, she said, and came after she realised she wouldn't otherwise have enough money to "live, study and keep my baby well".

Yesterday Turei said her admission had opened up a necessary conversation, and she had since heard from people in a similar position, or from people who knew people who had acted in a similar way out of desperation.

While she wasn't provided with details, Turei said she would never abuse the trust of those who disclosed information to her.

Prime Minister Bill English today said it is wrong Turei or any other politician to "essentially advocate breaking the law".

"I disagree with politicians essentially advocating breaking the law," English told reporters at Parliament today.

"If you come into Parliament you have the opportunity to change the law, to actually make sure you can change it you need to be in a Government.

"Of course people make mistakes - they inadvertently break the law, they do it under pressure," he said.

"It is the job of the police and then the justice system to take account of those circumstances, because life is a bit messy, it's not always black and white.

"But Ms Turei just seems to be getting a bit disconnected from the normal assumptions we make that people should keep the law and if they don't like the law they set out to change it."

Yesterday Turei said her admission had opened up a necessary conversation, and she had since heard from people in a similar position, or from people who knew people who had acted in a similar way out of desperation.

While she wasn't provided with details, Turei said she would never abuse the trust of those who disclosed information to her.

"I will never condemn a beneficiary for working as hard as they can to put food on the table and a roof over their head."

In an interview with RNZ National this morning, Turei talked about her circumstances while she claimed the benefit, including the fact that she had hadn't had a part-time job but had stood for Parliament while studying for her law degree in 1993 for McGillicuddy Serious and for the Aotearoa Cannabis Party in 1996.

"[Campaigning] took a little bit of time but this is the thing - people are entitled to have a decent life and I want every beneficiary to have enough money to be financially secure," Turei said.

Turei challenged Social Development Minister Anne Tolley in Parliament yesterday to offer an amnesty for current beneficiaries who were breaking the law.

Under the Green Party's new policy on welfare, it has promised to scrap all sanctions and work obligations for beneficiaries.