UPDATE: THE NSW government's plan to allow hunting of feral animals in national parks is set to cost taxpayers at least an extra $19 million.

Environment Minister Robyn Parker is set to announce the program's funding over five years, Fairfax reports.

The money will go towards 14 additional National Parks and Wildlife Service coordinators, new safety and regulatory signs, training of staff and education programs for shooters.

It would also fund compliance and education positions and extra resources for "monitoring and review to ensure the program has a positive impact on feral animal populations in our protected areas".

Premier Barry O'Farrell confirmed yesterday that ongoing discussions on risk assessment meant the program has been delayed to start in April.

The plan is part of a deal with the Shooters and Fishers Party, which saw the government pass legislation to allow recreational hunters to cull feral animals in the state's 79 national parks.

The controversial move has raised concerns that visitors to parks risk being accidentally shot by hunters.

Greens environment spokeswoman Cate Faehrmann said no amount of money would make amateur shooting in parks safe.

"The premier knows there is going to be a huge risk to public safety when national parks are opened up to shooters," she said in a statement.

"Now he is throwing money at the problem in a vain attempt to mitigate the risks.

"But what he should be doing is ripping up the deal and ending this embarrassing saga."

She said the $19 million that will reportedly go towards the scheme would be better spent on the National Parks and Wildlife Service.

"This money should be going towards properly resourcing our national parks to address the very real threats of weeds and feral animals instead of being wasted on this disgraceful deal," she said.