Claims that the national flag referendum is dividing the National caucus are "nonsense", Prime Minister John Key says.
An email from National MP Maggie Barry, which has been leaked to media, showed that MPs attended a meeting hosted by pro-change campaigner Lewis Holden this week.
Newshub reported it was a "crisis meeting" and that only half of National's caucus attended.
Mr Key said this afternoon that his caucus was free to vote for whichever flag it liked.
"I don't know what all this nonsense is about. MPs meet all the time about issues," he said.
"We don't have a caucus position because it's essentially a conscience view. Some MPs have said they support change, some don't."
Labour leader Andrew Little said he was not surprised the National caucus was not united on the issue, because polls showed most New Zealanders were against a change.
"I imagine National MPs are getting it in the neck from constituents, which is why they're getting a bit anxious-ridden about it.
"But the problem they've got, of course, is the train's left the station, the referendum's in a couple of weeks', I'm not quite sure what they think they can do about it."
A Herald poll last month found that five out of 59 National MPs opposed a change of flag, and 44 supported a change. The remainder were undecided.
• Silver Fern flag gets MPs' backing
The flag referendum will be held next month, when voters will choose between the existing New Zealand flag and a silver fern flag.