Prime Minister Bill English is now under pressure to take a tough stance in talks with US Secretary of State Rex Tillerson when they meet in Wellington next week.
Opposition MPs and local industry are condemning Donald Trump's move to pull the US out of the Paris Agreement.
Now Mr English is feeling the heat during a visit to Samoa, with Pacific nations hit the hardest by climate change.
Labour and the Greens say the PM needs to talk tough when he sits down with Mr Tillerson next week.
"When the world is looking for leadership on one of the most crucial issues facing the whole world, we should be very forceful," Labour leader Andrew Little says.
However, Mr Tillerson may not need much convincing, reportedly trying but failing to convince Mr Trump to stay in the agreement.
The US exit will also have financial ramifications. America contributes one third of the "Global Climate Fund" - which supports developing countries under threat - but now a big chunk of support money is now gone.
And then there's the domino effect.
"There's a risk that some countries might opt to do less saying that because America fails to provide leadership they will do the same," says Professor Alexander Gillespie.
When it comes to breaking global agreements - Mr Trump's move is unprecedented.
And while the US is keen to renegotiate, other countries may find themselves in the same boat - having to pick up the slack and do more.