Rio Tinto rejects NZ government offer of subsidy for smelter, says John Key NZ PRIME Minister John Key told TV3's Firstline program today that Rio Tinto has walked away from negotiations with the government over a short-term subsidy to help keep the country's only aluminium smelter open. They came back over the weekend and said no. We are rejecting the government's intervention and we will go back to continuing to talk to" state-owned power firm Meridian Energy, Mr Key said.