Legislation to extend paid parental leave to six months has been voted down in Parliament.
The bill in the name of the Labour Party MP Sue Moroney had the support of a majority of MPs.
But National Party whips cast three Maori Party votes in opposition on Wednesday night, despite the party having publicly said they supported it.
The bill failed at its second reading by 63 votes to 58.
Ms Moroney said she expects the vote to be corrected on Thursday and the bill to pass.