Climate campaigners say Junior Minister Martin Heydon is wrong to say agriculture climate targets can be met without a reduction in the national herd.
It comes after the publication of Ireland's first carbon budgets.
The Government will have to agree sectoral emissions targets in the coming weeks.
Thousands of farmers took to the streets of Cork at the start of the month to highlight their concerns on the climate bill and how it will negatively impact on farmers and their livelihoods
Junior Agriculture Minister Martin Heydon has suggested a cut in the national herd can be avoided by ramping up other climate mitigation measures.
But campaigner John Gibbons doesn't believe that.
"Claiming for example that we can achieve all of our agricultural targets with a stable herd and 'Ag-Climatise' - he's simply wrong.
"Now I know it's not palatable for some politicians to tell us the truth on this, but we really need to do better.
"Essentially we're getting people lining up to basically protect, as they see it, their sector."
