The NSW Greens have proposed an immediate moratorium on the destruction of koala habitat and the creation of a "Koala Super Highway" as part of their plan to save the species.
This would include "strong laws" to stop habitat being cleared on private land for development, agriculture and other purposes.
Launching the plan on Monday, Greens MP Cate Faehrmann said habitat destruction was the main driver threatening koalas with extinction in NSW by 2050.
"The government is still allowing their habitat to be cleared for logging, mining, agriculture and urban development," Ms Faehrmann said.
"We have the choice of allowing them to go extinct or bringing a halt to the destruction of their habitat, which is exactly what this plan aims to achieve."
Under the plan the Greens would map and protect existing koala corridors and revegetate destroyed or potential corridors to create a "Super Highway".
The party said it plans to introduce legislation to parliament after the March state election prohibiting the destruction of koala habitat for urban development, mining or agriculture on public or private land by 2025.
"The Greens also want to see a Great Koala National Park established as a matter of urgency," Ms Faehrmann said.
Labor said if it wins the next election it will commit $80 million towards a consultation process to determine the park's scientific and commercial value.
"The benefits of a Great Koala National Park are clear. That's why the Greens will get on with the job of making it instead of delaying with yet another review," Ms Faehrmann said.
Last week, the government announced a further $1.3 million investment in research projects under its $190 million NSW Koala Strategy.
"We set the ambitious goal to double the number of koalas in NSW by 2050," environment minister James Griffin said at the time.
"Koalas are both environmental and cultural icons for all Australians, which is why it's so important to conserve their habitat and secure their future in the wild."