A climate activist says New Zealand First's billion-dollar pledge for oil and gas exploration would be better spent on investing in renewables.New Zealand First announced at the weekend it would explore deep sea basins around the country for oil and gas if elected, saying that would shore up the country's fuel security.The party would invest an initial $1b into a national survey fund.Greenpeace chief executive Russel Norman said that money should instead be spent on investing in renewable electricity generation."That would actually give us energy sovereignty. It would mean cheaper energy and it would mean energy which doesn't destroy the climate."New Zealand had a "great opportunity for energy sovereignty" by investing more in renewables, Norman said.The billion-dollar fund was a gamble, and wouldn't guarantee power prices coming down, he said."It's a billion dollars you'd give to oil companies in the gamble that they might find something which might then be available in a decade's time, and then would destablise the climate."Demand for oil and gas in New Zealand and worldwide was dropping, he said."We've already seen it massively in China, with the electrification of transport. We're just starting to see it here."Winston Peters speaks at New Zealand First's campaign launch on Sunday.RNZ / Lillian HanlyAt New Zealand First's campaign launch on Sunday, leader Winston Peters said one of the most concerning issues facing the nation was fuel security and supply.Peters said New Zealand potentially held Norway-scale energy prospects which had never been properly surveyed."If we identify those reserves in our basins, we will have the ability to utilise the natural resources we have to make our country secure, prosperous and to build real resilience."He said within six years, the country could have a pathway to own and control its own supply of energy.The party would place a royalty above 50 percent on all extractions as production matured.National energy spokesperson Simeon Brown said the policy was a reminder that Winston Peters and Shane Jones supported a ban on oil and gas when in government with Jacinda Ardern."New Zealand had a thriving oil and gas industry, before Winston Peters and Shane Jones did a deal with labour and the Greens to ban offshore exploration."