National says the buck stops with Prime Minister Jacinda Ardern - over the Government's $30 million Ihumatao buy-up.
The Auditor-General's found the purchase was unlawful, until it's validated by Parliament.
Housing spokesperson Nicola Willis says Ardern needs to assure Kiwis the Government's learned its lesson - and that ministers will apologise.
She says Ardern must also ask deputy Grant Robertson about how this could happen.
“This has Robertson's fingerprints all over it - as he was the face of the settlement.
"As Minister of Finance, he has ultimate responsibly over the use of taxpayer funds.”
Housing Minister Megan Woods is defending the Government's purchase of Ihumatao.
Woods told Heather du Plessis-Allan incurring expenditure without the proper authority is not unusual - and happened 71 times over the past five years under the National Government.