Moderate Liberals have seized on Scott Morrison’s apparent shift on climate change policy to argue the government will do more to cut emissions, as some conservatives push back against any “symbolism” that could damage the economy.

In a sign of the challenge facing the prime minister as he seeks to “evolve” climate change policy, government MPs have split over the prime minister’s comments on the weekend that the Coalition wanted to reduce emissions “even further” than current commitments.

While saying Australia’s 2030 emission reduction targets remain government policy, Morrison said he wanted to do “better” and would only rely on the use of carryover credits from the Kyoto protocol if needed.

Australia is the only country relying on carryover credits to meet its Paris 2030 target of 26% to 28% of 2005 levels by 2030, which critics say do not represent the cuts required to limit global warming to as close to 1.5C as possible.

Katie Allen, the Liberal MP for the Victorian seat of Higgins, welcomed Morrison’s remarks, telling her constituents that she would be a “strong voice” in the party room for stronger action on climate change.

“I’m excited we are starting to move in the right direction – but we have a lot more to do,” Allen told her supporters on Facebook.

“I have been and will continue to be a strong voice for Climate Action inside the tents.”

When asked if she supported the aim of net zero emissions by 2050 and lifting “clean energy ambitions” in line with the global efforts to keep the world below 1.5C warming, Allen said she agreed more needed to be done.

“I’m working on influencing that agenda. We need to have higher ambitions to lead the world in renewables – not just to drive down our own emissions but help other countries with theirs,” Allen said.

“We have a diplomatic strength that should be used to help strengthen the global agenda on climate action.”

The self-styled modern Liberal MP Tim Wilson also endorsed Morrison’s comments, saying the commitment at the last election to “cut emissions, but not jobs” was a baseline for action.

“The prime minister has rightly identified there’ll be more evolution of policy to cut emissions, but not jobs, and I look forward to contributing to that important evolution,” Wilson told Guardian Australia.

Dave Sharma, the MP for Malcolm Turnbull’s former seat of Wentworth, said he was “pleased to hear” Morrison’s comments on the importance of responding to climate change and promoted the government’s plan to “continue to evolve our policies with a view to reducing our emissions further”.

Quick Guide Climate change and bushfires Show Does climate change cause bushfires? The link between rising greenhouse gas emissions and increased bushfire risk is complex but, according to major science agencies, clear. Climate change does not create bushfires, but it can and does make them worse. A number of factors contribute to bushfire risk, including temperature, fuel load, dryness, wind speed and humidity. What is the evidence on rising temperatures? The Bureau of Meteorology and the CSIRO say Australia has warmed by 1C since 1910 and temperatures will increase in the future. The Intergovernmental Panel on Climate Change says it is extremely likely increased atmospheric concentrations of greenhouse gases since the mid-20th century is the main reason it is getting hotter. The Bushfire and Natural Hazards research centre says the variability of normal events sits on top of that. Warmer weather increases the number of days each year on which there is high or extreme bushfire risk. What other effects do carbon emissions have? Dry fuel load - the amount of forest and scrub available to burn - has been linked to rising emissions. Under the right conditions, carbon dioxide acts as a kind of fertiliser that increases plant growth. So is climate change making everything dryer? Dryness is more complicated. Complex computer models have not found a consistent climate change signal linked to rising CO2 in the decline in rain that has produced the current eastern Australian drought. But higher temperatures accelerate evaporation. They also extend the growing season for vegetation in many regions, leading to greater transpiration (the process by which water is drawn from the soil and evaporated from plant leaves and flowers). The result is that soils, vegetation and the air may be drier than they would have been with the same amount of rainfall in the past. What do recent weather patterns show? The year coming into the 2019-20 summer has been unusually warm and dry for large parts of Australia. Above average temperatures now occur most years and 2019 has been the fifth driest start to the year on record, and the driest since 1970. Is arson a factor in this year's extreme bushfires? Not a significant one. Two pieces of disinformation, that an “arson emergency”, rather than climate change, is behind the bushfires, and that “greenies” are preventing firefighters from reducing fuel loads in the Australian bush have spread across social media. They have found their way into major news outlets, the mouths of government MPs, and across the globe to Donald Trump Jr and prominent right-wing conspiracy theorists. NSW’s Rural Fire Service has said the major cause of ignition during the crisis has been dry lightning. Victoria police say they do not believe arson had a role in any of the destructive fires this summer. The RFS has also contradicted claims that environmentalists have been holding up hazard reduction work. Photograph: Regi Varghese/AAP

Another moderate Liberal, Jason Falinski, said the party would continue to “drive responsible policy on climate change”.

“We need practical and sensible policy here and seek ambitious action globally,” he said.

But as moderates welcomed the shift, conservative MPs were warning against a change in policy.

The Queensland Nationals MP Llew O’Brien told the Courier Mail that if Australia went beyond its current commitments, it would be “pure symbolism at the expense of the economy”.

The former Nationals leader Barnaby Joyce also issued a thinly veiled warning that the government risked a backlash in the bush if it moved to ramp up emission reduction targets.

“To the person in the weatherboard and iron, the solution is not: you’ll lose your job and we’ll put up your power prices, because that is not a solution, that is another problem,” Joyce told Guardian Australia.

Joyce said the royal commission into the bushfires needed to be “absolutely pragmatic” in its focus, looking at how to prevent a repeat of the crisis without straying to “global” issues.

“If it goes off on a path of a macro global view, it will not ultimately bring people together, it will tear people apart,” he said.

“Global outcomes must be managed globally.”

The divide comes as Morrison insists the role of climate change is “not in dispute” within his ranks, despite several MPs denying the role of a warmer planet as an underlying cause of the severe bushfire season.

The Nationals MP George Christensen was the latest to promote his view that climate change was not a factor, telling his supporters on Facebook that climate change is not “a bogey man who can go around lighting bushfires”.

“I post this because those who are politicising this tragedy by pushing their extreme green political agenda while the fires still burn absolutely disgust me,” he said.

The Liberal MP Craig Kelly last week caused a storm of controversy after appearing on UK television to argue that there was “no link” between climate change and Australia’s drought.

Following the appearance, Morrison told his MPs that backbenchers should not do any international media interviews.