Council staff said the likely cost was about $70,000 but it could be shared with the Whangārei District Council. They also said the potential cost to the council and Northland agribusiness could run into millions of dollars if GMOs were released.
Deputy mayor Tania McInnes, who chaired Thursday's council meeting, said she hoped a new regional council would reconsider, averting the need for a costly appeal.
''I'm sure everyone's aware it's caused quite a backlash,'' she said.
Councillor John Vujcich said he understood the possible advantages of the technology, in medicine for example, but he was concerned about the financial risk if the council did not adopt a precautionary approach to releasing GMOs into the environment.
''The council is generally the last man standing, and I'd hate the council to face millions in legal action from organic farmers who've gone under.''
Kerikeri organic farmer and GE-Free Northland spokesman Marty Robinson welcomed the district council's decision, saying it showed the regional council was ''out of touch'' and not listening to its constituents.
The regional councillors whose votes saw GMO precautions left out of the Regional Plan defended their decision by saying the technology could some day provide New Zealand with solutions to environmental challenges such as kauri dieback or introduced pests, or help reduce greenhouse gases without undermining the economy.
It's not the first time there has been legal action between the Far North District and Northland Regional councils but usually it's the other way around.
In April the regional council took the district council to the Environment Court for ongoing breaches of its consent conditions at Paihia's sewage plant.