Scott Morrison has signalled the Australian government will not increase its efforts to combat climate change despite an extended bushfire crisis and a record-breaking heatwave.

Returning to work on Sunday after a controversial family holiday in Hawaii, the Australian prime minister apologised for his absence on top of the mea culpa he offered on Friday while still overseas.

At a press conference after a visit to the New South Wales Rural Fire Service headquarters in Sydney, Morrison called on Australians to “be kind to each other” and reject division – but then accused those who want more action against global heating of political point-scoring.

Morrison acknowledged that his absence – leaving deputy prime minister Michael McCormack in charge since Monday – had caused “great anxiety” and said if he had his time over he “would make different decisions”.

Morrison asked Australians to be “fair-minded”, arguing he went on holiday to keep a promise to his children, and put a positive spin on the widespread community backlash at his absence.

“I am comforted by the fact that Australians would like me to be here simply so I can be here alongside them as they go through this terrible time,” he said.

“And so to those Australians who ... I had caused upset to I apologise for that.”

Morrison then sought to turn the page on the episode by unilaterally declaring “the time for that discussion is over”.

Morrison said there was “no argument” about the links “between broader issues of global climate change and weather events around the world” but it was “not a credible suggestion” to make a direct connection to any single fire event.

Global heating is leading to longer, hotter, drier summers which experts agree increases bushfires’ frequency and severity. But Morrison said it was “one of many factors”, listing others including backburning, vegetation management, building codes, carelessness, arson and lightning strikes.

On Saturday, McCormack said he “absolutely” agreed that “further action” to combat climate change is needed.

Morrison appeared to snuff out hope his government will improve its policies, which have caused Australia to be rated worst out of 57 countries for its handling of climate change by a group of thinktanks.

“I do not accept the suggestion that Australia is not carrying its weight,” he said.

Morrison claimed that McCormack was “making exactly the point I’m making” – citing existing commitments in the Paris agreement to decrease Australia’s emissions by 26% by 2030 – although he also suggested there may be room for “further refinement” before 2030.

Australia needs to cut emissions by 695m tonnes cumulatively across the next decade to meet its 2030 target. The Morrison government has said more than half of that cut, 367m tonnes, will come from accounting – using carryover credits from meeting earlier Kyoto targets – and not from practical emissions reduction.

The centrepiece of Australia’s policy is a $2.55bn fund to pay polluters to reduce emissions, after the Liberal-National government abolished Australia’s carbon price in 2014.

Asked about the use of carryover credits, Morrison replied that “people can expect my government to do what it promised to do, what it took to the last election”.

“I know there are some who tried to make political points and score points over these issues in the midst of these disasters and that is disappointing.”

Morrison said the government would not act in a “knee-jerk, crisis or panicked mode” – likening his refusal to increase ambition on climate change with the steady professionalism of those managing the bushfire emergency.

“A panic approach and response to anything does not help. It puts people at risk.

“Not just their livelihoods but, I mean, if you walk out there into the control room you will not see people panicking, you will see people be very professional, very focused on the job they have, talking to each other in a very professional way and getting the job done. Government’s the same thing.”

Minutes after calling for an end to division, arguing, partisanship and point scoring, Morrison said the Coalition is reducing emissions without the “reckless job-destroying and economy-crunching targets that others are seeking to force upon us”.

The government’s own projections show Australia is on course for 50% renewables by 2030 – a target which Morrison labelled as reckless and economy-wrecking in the May election campaign.

Morrison flagged that he will discuss resourcing for future emergency management with states and territories at a meeting in March.

Morrison said the government is considering calls to pay volunteer firefighters, but noted that is “in the first instance” a matter for state governments.

Morrison later visited the families of Geoff Keaton and Andrew O’Dwyer, two volunteer firefighters killed late on Thursday near the town of Buxton, and conveyed his sympathies.

Labor leader Anthony Albanese told reporters in Sydney it was a “good thing” Morrison is back but there was “no change” in the prime minister’s approach to the bushfires or climate change.

“The deputy prime minister yesterday said [that] new measures were needed … and today, going from the acting prime minister to the real prime minister, we have a dismissal of the need for any action on climate change,” he said.

Albanese said Morrison’s holiday was “a matter for his judgement”. “He chose to leave. He chose also to do it in a way that I think created a major issue of secrecy.”

Earlier, the NSW premier Gladys Berejiklian and federal emergency management minister David Littleproud announced an additional $3.5m of disaster recovery funding to the Wingecarribee and Wollondilly local government areas.

The commitment brings the total federal-state recovery fund to more than $63m.