The New South Wales environment minister Matt Kean has called on fellow Liberal moderates in Canberra to replicate the forceful lobbying of National MPs, and insist that Scott Morrison takes a net zero target to the Cop26 in Glasgow.

Kean has warned in an interview with Guardian Australia’s politics podcast that traditional Liberal voters are prepared to rise up against Liberal governments failing to take ambitious action to reduce emissions and transition to a sustainable economy.

The interview follows NSW this week unveiling a new pledge to halve emissions in the state by 2030. The previous state target was a 35% cut compared with 2005 levels.

The new commitment spearheaded by Kean was backed by Liberals and Nationals in cabinet – while their federal counterparts remain publicly split on climate policy in the lead up to the Glasgow conference.

With the Cop26 bearing down, the NSW minister and prominent Liberal moderate says colleagues in Canberra need to find their voice, and quickly. “I think sensible Liberals need to make their position very clear to the prime minister just as Matt Canavan, George Christensen and other characters make abundantly clear their views on these issues.”

“They never worry about rocking the boat, so why should progressive, economically rational Liberals not do likewise? We should be standing up for our constituencies, we should be standing up for our country and we should be making our voice known in the Liberal party and in the public domain.”

Kean believes Scott Morrison should adopt the mid-century net zero target, and also commit to a more ambitious medium-term emissions reduction target.

Courtesy of the NSW commitment, and with other states contributing to the heavy lifting on emissions reduction, Morrison would now be in a position to unveil a 34% cut in national greenhouse gas emissions by 2030 based on existing pledges, rather than sticking to the current national 2030 target of a 26 to 28% cut.

There has been sustained speculation that Morrison could update the 2030 pledge as well as committing to net zero, assuming the Nationals can be persuaded. But the scenario considered more likely is Australia will predict overachievement on the existing target rather than adjust the current pledge.

The NSW environment and energy minister said the coming transition should be viewed through the lens of economic opportunity rather than cost. In electoral terms, he says the threat in the Liberal party’s electoral heartland is real, with groups like Climate 200 promoting independent candidates.

“The number one issue in my community is taking action on the environment that also helps our economy, and that should be completely in line with what conservatives, who are meant to be conserving things, should be about: conserving our planet, handing it to the next generation better than we found it, but also seizing the biggest economic opportunity that we will ever see,” Kean said.

“I don’t want to see strong, good Liberal moderates thrown out and replaced with independents.”

“Strong economically rational and socially progressive voices in the Liberal party can bring about change for the better and that’s what we are doing here in New South Wales”.

“I want those people to stand up in the Liberal party and be counted and then they won’t have an issue from independent voices looking to knock them off in a general election”.

The Morrison government is expected to unveil its commitments for Glasgow by mid-October. Some Queensland Nationals have signalled they are implacably opposed to net zero.

Federal Liberals in metropolitan seats have called publicly for Morrison to adopt the net zero commitment. A number of these MPs would also support a higher medium term emissions reduction target.

Given the opposition from some Nationals, government MPs say the federal minister for energy and emissions reduction Angus Taylor has privately floated the idea that the Coalition could adopt a plan to get to net zero without signing up to the target. But many Liberals regard this idea as completely suboptimal in a policy sense, and politically untenable.

• Sign up to receive an email with the top stories from Guardian Australia every morning

Guardian Australia revealed earlier this week Morrison met on Tuesday with a deputation of Liberals in a teleconference – including Dave Sharma, Fiona Martin, Trent Zimmerman, Julian Leeser, John Alexander, Julian Simmons, Angie Bell, Paul Scarr, Andrew Bragg, Tim Wilson, Katie Allen, Dean Smith, Jason Falinski, Celia Hammond and Bridget Archer.

The prime minister is understood to have told the group it remained his preference to land a roadmap laying out the required technology, actions to get to net zero emissions by mid-century and the 2050 target. Morrison also acknowledged that climate change was now a vote-changing issue in the Liberal party heartland.