National Leader Judith Collins says she'll do her best to meet the Government's new 2030 climate change target if she is Prime Minister - but she isn't making any promises.
The Government has committed to up New Zealand's emissions reduction pledge (called an NDC) from the 30 per cent net reduction pledged by National after the Paris Agreement, to a 50 per cent net reduction by 2030.
Both targets are measured against gross emissions levels in 2005.
"We're a bit critical of it because it's a huge ask in 9 years to go from a 30 per cent reduction to a 50 per cent reduction," Collins said.
She did not rule out changing the target if National won the election, but said this was unlikely because Governments have to be "careful" before they back out of international agreements.
"We are concerned about it - whether or not we'd change it, well, we'd have to see," Collins said
"It's important that we - if we are signed up to commitments - we'll try and meet them but I have to say this is going to be a big ask for a little country.
"The problem is it's an international deal - you've got to be careful before you go changing things."
The pledge will require the Government to offset New Zealand's high emissions by paying to reduce emissions in other parts of the world and counting those emissions reductions towards its target - most of the emissions reductions for the current NDC will actually come from offshore.
Climate Change Minister James Shaw said modelling had put the cost of such schemes at about $900 million to $1.5 billion a year.
Collins said she was concerned about the cost of these offset schemes.
She said she did not favour new taxes that would help pay for the offsets.
"This Government has indebted the country - some things they've had to around Covid we understand that but right at the moment one of the very few productive sectors that is creating wealth for the country and paying the bills for paying back the money that's been borrowed and paying for healthcare and for education is actually agriculture.
"We don't favour more taxes at a time when the country is being beggared by debt and we need to be grown up about this."