Green Party co-leader Metiria Turei says she has decided to pay back any money owed to Work and Income but is waiting to hear from them to find out how much she needs to pay.
Turei said there was "no doubt" the Ministry of Social Development (MSD) would investigate her case and she expected a call any day now.
"I've left them no option," she told the Herald. "Of course they need to have a look."
Announcing her party's welfare policy at the party's AGM on Sunday, Turei revealed that she lied to Winz about her living situation while on the domestic purposes benefit in the 1990s.
She admitted that she had extra flatmates living with her to help pay the rent, but did not tell the authorities because her benefit would be cut. A solo mother at the time, she feared she would not be able to care for daughter Piu if she lost her welfare payments.
Turei initially said she would pay it back if MSD got in touch, but later said she planned to refund Winz regardless.
"It was always the decision to pay it back, I just wasn't clear enough in the speech on Sunday.
"But I need to wait for WINZ to do the calculation and the investigation, because I can't do that myself."
It was difficult to know how much she owed, she said. She had extra flatmates in three of the five flats she lived in, over three years.
Turei was applauded by some for her confession, but also faced a backlash from some members of the public who were angry that she used fraud to make a political point.
She admits that a few members of her party were upset with her admission, and that some of the details of her party's welfare policy had been pushed into the background.
But overall, she said it had been a positive move because it had started a conversation about the flaws of the welfare system and the mistreatment of beneficiaries.
"I expected all of the criticism," she said. "But I didn't expect anything like the support I've got."
Other current or former beneficiaries have shared similar stories of their experience of the welfare system. Some of them have posted them on social media under the hashtag #IAmMetiria.
"This is the conversation we need to be having." Turei said. "What people are talking about is how bad it is to be on a benefit, how financially insecure, how despairing."
While Turei welcomed the show of support, she was also worried that people who were still on welfare had exposed themselves to sanctions from MSD.
"That's my big concern now. There's been suggestions before that MSD follows social media accounts."
"And this is what was at the heart of my speech, that people are so ground down because of that threat of poverty that's used against them."
MSD indicated earlier this week that it was likely to look into Turei's case. It would not comment further today. The police referred questions to MSD.