International tourists will be charged twice as much as New Zealanders to stay overnight along the country's top five walking tracks if National is re-elected.

Photo: RNZ/Tracy Neal

The party's leader, Bill English, and conservation spokesperson, Maggie Barry, made the announcement in Queenstown this morning.

"The nine Great Walks are among New Zealand's most popular visitor attractions, but they run at an $1 million annual loss," Ms Barry said in a statement.

"We believe it's fair that international visitors who experience our Great Walks pay a little more to enjoy our landscape and contribute to protecting our native wildlife."

The fee increase would apply to the Milford, Routeburn, Kepler, Abel Tasman and Tongariro walks - the five most popular tracks - from October 2018.

Tourists visiting other walking tracks would face a 50 percent fee increase. There would be no fee increase for New Zealanders.

Increasing the charges for tourists would raise an extra $4m, which would be used to maintain the walks, Ms Barry said.

"New charges will also apply to the under-construction Paparoa Track and the two new Great Walks planned as part of Budget 2017's $76m investment in conservation," she said.

"National will also close a loophole which has seen international school parties book out huts without paying, by introducing a charge for teenagers and children from overseas."

It currently costs $70 to stay in a hut on the Milford Track and $65 for a hut on the Kepler Track during the peak summer season.

In a separate announcement, National said it would also double the funding that goes to the Department of Conservation's community programmes, to $10m a year.

More to come