NZ Transport Agency chief executive Fergus Gammie has tendered his resignation, which has been accepted by the board.
Gammie has been under fire since it was revealed that the NZTA had not been carrying out its regulatory function properly, resulting in thousands of vehicles so far having to be retested for warrants of fitness.
In a statement, Gammie said that by stepping aside he was hopeful that the necessary review and improvement of the regulatory function at the NZTA could be completed without any distraction.
"As I said in October, the Transport Agency has long been focused and reliant on education and self-regulation rather than focusing attention and resources on ensuring regulatory compliance and enforcement. I also said that the public can expect that an increased number of enforcement actions would be taken to ensure compliance," Gammie said.
"In resigning, I note that the approach and focus of the Transport Agency has necessarily changed. I ask that full support be given to the board, management team, and Meredith Connell as they work towards resolving the outstanding issues and towards developing a stronger regulatory enforcement framework to ensure the public has confidence in the Transport Agency's processes," Gammie said.