National's attempt to allow both parents of a new baby to take paid parental leave at the same time has failed.
It put up an amendment to the bill that extends paid parental leave which would have given parents the choice, but it was defeated by 61 votes to 57 in parliament on Tuesday night.
National MPs argued it could suit new parents to both be at home at the same time to look after their baby - particularly if they had twins.
The bill extends paid parental leave from the current 18 weeks to 26 weeks by 2020.
Either parent can use it, but not both at the same time.
The minister in charge of it, Iain Lees-Galloway, said the proposed amendment would allow parents to take 13 weeks leave at the same time, using up all their PPL.
"We want a parent at home as long as possible, the purpose is to allow a baby to bond," he said.
But he hasn't rejected the idea entirely, and said it could work for the first few weeks after a baby had been born.
Mr Lees-Galloway offered to work with National "to see if we can come up with something that works".
He said National's proposal was a different policy issue and didn't fit into the bill.
Under the bill PPL will increase to 22 weeks in July next year and to 26 weeks in July 2020.
It was a campaign promise and the bill was introduced under urgency last week.
National supports the bill and It's likely to be passed into law later this week.