Big names in the industry like Bel Group, Danone, Lactalis US and Nestle committed at COP28 this week to publicly disclosing their dairy-related methane emissions and drawing up detailed plans of action.
The commitment is in partnership with global nonprofit, Environmental Defence Fund (EDF).
Fonterra director of sustainability Charlotte Rutherford said they had talked with the EDF and continue to engage with them, but the timing was not quite right for the dairy co-op.
"Our recent focus has been on announcing our on-farm emissions target and working with farmers to help them understand this.
"We decided that the timing just wasn't quite right as it may cause confusion - this doesn't mean that we're not committed to reducing methane, which is why our work through AgriZeroNZ to find a solution to methane is so important."
Dairy Farmers of America and Danish dairy giant Arla also did not sign the agreement.
But Nestle - Fonterra's biggest customer - did, so what implications are there for Fonterra?
Rutherford said Fonterra looked forward to partnering with Nestle to achieve its ambitions.
"They are complementary to ours, we report on our methane emissions as part of our on-farm emissions life cycle assessment annually and our recently released climate roadmap and emissions reduction targets also support our customers like Nestle with transparency for their own reporting."
On Sunday, New Zealand was awarded the first "fossil of the day" award of COP28 - a mark of dishonour in recognition of the new government's decision to reverse the ban on offshore oil and gas exploration.
