Environment Minister Sussan Ley has been trawling federal environment laws to find a provision to direct the NSW government to crack down on the damaging animals.

"Seeing the damage that feral horses have done to the park now makes me extremely angry," she told the National Press Club in Canberra on Wednesday.

NSW scrapped plans to cull 90 per cent of the feral horse population after the state Nationals leader John Barilaro campaigned against it in 2018.

But Mr Barilaro - the deputy premier - has since acknowledged the need to reduce brumby numbers and the state government is due to release a new management plan soon.

Ms Ley said the horses were damaging a fragile and unique ecosystem within the national park.

"I don't want point fingers at another government and say you should do more but I'm very happy to have a direct conversation," she said.

"We must collectively do more. I appeal to everyone who feels strongly about this issue to make their voices heard."

The Albury-based federal minister said her stance was not popular among some of her coalition colleagues or people in her electorate.

Pro-brumby campaigners have previously invoked The Man From Snowy River's place in Australia's cultural folklore as a reason to oppose culls.

"What also frustrates me is a lack of understanding but I'm happy to say that people are moving in this direction," Ms Ley said.

Australian Associated Press