Parliament has passed the Crown Minerals Amendment Bill, putting an end to new offshore oil and gas exploration.
The bill passed by 63 votes to 55.
The Green Party said it was "an essential first step in winding down offshore exploration for new sources of fossil fuels''.
The change comes on the back of an announcement in April by the Prime Minister - which some in the sector said they were blindsided by.
The National Party has pledged to reverse the ban if back in government.
New Plymouth Mayor Neil Holdom said it was now time for the government to step up and invest in a transitional plan away from fossil fuels and fund alternative energy projects while "keeping the lights on" in New Zealand.
He told Morning Report he was seeking a meeting with Energy Minister Megan Woods and Finance Minister Grant Robertson to see if the government will invest in a "just transition".
He believed in zero carbon targets, but said there was still a need for gas supplies when falling lake levels impacted on hydroelectricity energy production, which created spikes in market prices.
"What the government has done is they've taken a pothole a one section of the supply side," he said.
"We would have thought they'd have naturally done that with coal, but for some reason coal seems to have got a leave pass and they've gone 'we're going to go after oil and gas'."
"Now our view is you put a price on carbon and you slowly increase that price and then all of these other technologies become viable.
"So we're saying to the government, look put your money where your mouth.
"Why not take the Crown mineral royalties, that you're taking out of Taranaki, about $3 million dollars a week, and put it into a transition fund for the people of Taranaki to invest in the kind of technology and educational capability that will get us there."
As an example, he said he had a meeting with a company who had a fully-tested tidal energy prototype and they were seeking government funding.