A climate expert has claimed the Government's reduced methane targets are 'unambitious'.

The goal for 2050 has been slashed to a range of 14-to-24 percent below 2017 levels - about half the former target.

Agricultural methane emissions won't be taxed.

Victoria University's Nathanael Melia says by investing more into research, New Zealand could have aimed for higher.

"We're using brand new science and brand new thinking to find out what we should do with our unique makeup to do these sorts of things. We're being a leader here and I think the Government could have been a bit more of a leader."

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