NZ First leader Winston Peters says the prime minister’s belief that overseas shoppers will pay a premium for New Zealand meat raised under the new methane emissions pricing scheme is “bovine scatology”.

“Apparently Greta in the supermarkets of Europe is going to search the shopping aisles for a 35% more expensive product because the PM said so,” he said.

That, he said, was “bull dust”.

New Zealand farmers, he said, have the lowest carbon footprint in the world now. “Don’t get this wrong: for every cow that we lose, our overseas competitors will replace it with one with a higher carbon footprint.

“You do the maths, because this government and its cohort can’t.”

Speaking to the New Zealand First annual conference in Christchurch, Peters said New Zealand was heading for disaster with its immigration overhaul, blaming “lily-livered liberals espousing policies against New Zealand’s interest when it comes to immigration”.

“We’ve always believed that immigration is really based on one fundamental principle: bringing people to New Zealand who we need, not who need us.”

On the economy, Peters said New Zealand should have a laser focus on increasing growth. “Incentivising IT and industry, production, innovation, creativity, technology adoption and international connectivity. All these things should be part of our conversation.”

In his focus on growth and productivity, Peters was echoing UK prime minister Liz Truss, who has also called for action to improve her country’s sluggish growth rate. However Peters criticised Truss’s focus on tax cuts to kickstart the economy.

“Everybody here believes in tax cuts,” Peters said. “Everybody in this room believes in tax cuts, and it is possible – if you grow the economy rapidly [first].”

Earlier today, the conference voted unanimously for a policy of adjusting tax brackets to automatically adjust in line with inflation.

National’s has the policy, but NZ First is calling for the adjustments to catch up with inflation over the past decade. National wants the adjustment to factor in inflation over the last four years only.