The World Wildlife Fund (WWF) claims the Government's Fast-Track Approvals Bill could threaten New Zealand's free trade agreement with the EU.
Aotearoa's agreement with the EU comes into effect from Wednesday.
"The terms of this deal are considered gold standard internationally," WWF New Zealand chief executive Kayla Kingdon-Bebb said of the NZ-EU free trade agreement (FTA) on AM on Wednesday.
"We must not weaken or reduce our environmental laws to encourage trade or investment and, from the early days of this term of Government and in their own words, it has become... clear that their intention is to slash red and green tape [and] reduce environmental protections to boost export-led growth - in direct violation of the terms of this agreement.
"There are also specific clauses throughout the FTA on things like the Paris Agreement commitments [and] on new mining development that are much more specific in terms of what each government has agreed to do - and if you want to take the Fast Track Approvals Bill as an example, the consideration in the EU FTA around public involvement in new mining applications is very clearly not met in the context of that legislation."
But the Government said in a statement it wasn't concerned and did not believe the Fast Track Approvals Bill would contradict New Zealand's FTA commitments with the EU.
Trade Minister Todd McClay said all agreements recognised New Zealand's right to set its own environmental laws.
Both New Zealand and the EU were two of the most committed in the world to the Paris Agreement, said European Union Ambassador to Aotearoa Lawrence Meredith.
"What we should really be talking about there is that this agreement is the most ambitious sustainable development chapter seen in a European Union free trade agreement so far and, indeed, will really set standards that should reassure citizens - both from the European Union and New Zealand - that both parties are strongly committed to climate neutrality," he said, appearing on AM after Dr Kingdon-Bebb.
The FTA coming into force was a historic milestone after years of negotiations between New Zealand and the European bloc.
It also marked a significant leap forward for Kiwi businesses, which would have greater access to the European market.
"I think it's a really important opportunity for exporters and consumers - both in the European Union and New Zealand," Meredith said.
