The National Party says its candidate selection process for the Rodney electorate will begin again to ensure it is beyond reproach.
The move follows claims of infighting and allegations of attempts to skew the process.
Five people had been seeking nomination to replace Speaker Lockwood Smith as the MP for Rodney.
Dr Smith is retiring from politics at the general election in November.
National Party President Peter Goodfellow says the party board has agreed that the slate should be wiped clean and the candidate selection restarted.
He says it is not for him to pass judgement on the claims that have been made about the selection process to date, as he has not been involved in it.