What happens in National's caucus meeting, stays in National's caucus meeting -- including on the issue of water fluoridation.

National is backing Government plans to shift the decision from local city and district councils to the Ministry of Health, provided DHBs are consulted.

Leader Judith Collins has dismissed reports that she opposed the party's position.

Speaking on Politics Wednesday with Mike Hosking, National MP Mark Mitchell says caucus made its decision based on the science, but he can't discuss who said what behind closed doors.

"I have no idea, we don't know who talks to who in the Press Gallery. We're just focused on our job of holding the Government to account." 

He says the party wants to see District Health Boards consulted, but he won't say how specific MPs voted.

"The science shows that clearly there's health benefits to having fluoride in our water, especially for our children, and that's where caucus landed on it."

Meanwhile, there could be a little bit more relief on the way for struggling tourism operators.

Tourism Minister Stuart Nash is visiting Kaikoura today -- in the latest stage of his national tour of holiday hotspots.

He says the trip will include an announcement about part of a new tourism initiative.

Nash told Mike Hosking he'll also be meeting with local operators, about how they're coping during the border closures.

"To get a feel for how things are on the ground, to visit them, to show the Government does absolutely support them 100 percent."

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