Julie Anne Genter was brought to tears during James Shaw's speech on the Zero Carbon Bill when he delivered a message to the next generation.

Shaw, the Minister for Climate Change and co-leader of the Greens, delivered the first speech in Parliament on Thursday for the Zero Carbon Bill's final reading.

He spoke about how tackling climate change is "too big for politics", and that he has "fought the centrifugal forces of politics to try and create bipartisan consensus and support" for the legislation.

It was near the end of Shaw's speech when his Green Party colleague, Genter, appeared to get emotional, turning to Green MP Golriz Ghahraman to say, "I think I'm going to cry."

Shaw had just mentioned that he'd become an uncle to his newest nephew, Luka.

"I hope that when you are older, you look back on this day and you know we did our best for you," Shaw said. "In this House today, your House, we see you all and we deliver this Bill for you. Let us begin."

Genter told Newshub Shaw's speech made her think of her one-year-old son, and her brother's first child expected to arrive in March next year.

She said it made her think of "all of their generation, who are relying on us to take responsibility and do what is needed to keep global warming below 1.5degC".

Genter said the Zero Carbon Bill is an "important first step", and said New Zealand "needs to keep up the momentum".

"There are so many opportunities to reduce harmful climate pollution and create a better future for our kids. We can change things for the better. We must."