Jacinda Ardern has accused Simon Bridges of having no "credibility" during a debate over KiwiBuild prices in Parliament today.

The Prime Minister wasn't impressed with the National Party leader's assertion that New Plymouth KiwiBuild houses will be sold at $100,000 over the median house price in the area.

"Is she aware her houses in the New Plymouth KiwiBuild development are going to cost around $100,000 more than the median house price in the area?" Mr Bridges asked during Question Time today.

Ms Ardern then attempted to blame the previous National government for neglect in the area, saying the KiwiBuild announcement has been welcomed by those in the community.

"If he's talking about the area that was absolutely neglected, shamefully by that last government, state houses in a dire need, we need a rejuvenation in that community.

"It has been widely welcomed by the New Plymouth community because we not only need affordable houses we also need more and better state houses," Ms Ardern countered.

Mr Bridges continued to press for an answer on whether or not the KiwiBuild homes would be $100,000 more than median house prices, which drew a blunt retort from the Prime Minister.

"I'm not going to answer questions based on assertions by that member, if the member had a little bit of credibility in the way he has used numbers in previous questions then perhaps I would," Ms Ardern said referencing a previous debate on rent figures between the pair.

Housing Minister Phil Twyford had previously acknowledged that with a maximum price tag of $450,000 the 68 KiwiBuild homes would be out of the reach of many current Marfell residents.