The shadow climate change minister, Mark Butler, has slapped down fellow frontbencher Joel Fitzgibbon, declaring Labor cannot support the Coalition’s 2030 emissions reduction target because it is inconsistent with the Paris agreement.

Fitzgibbon, who suffered a significant swing against him in his coalmining seat in the Hunter Valley in the May election, used a speech on Wednesday to argue the ALP should offer “a political and policy settlement” on climate policy “to make 28% the target by 2030”.

The Morrison government’s 2030 target is a 26%-28% reduction on 2005 levels by 2030. Labor at the last election proposed an emissions reduction target of 45%.

Fitzgibbon told the Sydney Institute Labor had suffered too much political damage attempting to be ambitious on climate policy.

“Labor needs to reach a sensible settlement on climate change,” the shadow resources minister said. “How many times are we going to let it kill us? Indeed, how many leaders do we want to lose to it?”

But Butler told Guardian Australia Labor would not adopt Fitzgibbon’s proposal.

“As I’ve said a number of times since the election, we remain committed to implementing the principles of the Paris agreement, which are to keep global warming well below 2C and pursue efforts around 1.5C,” the shadow climate change minister said.

“We will have a mid-century target of zero emissions and medium-term targets which are consistent with the agreement – and the government’s target, which was developed by Tony Abbott with no expert advice, is fundamentally inconsistent with the Paris agreement.

“It would lead to global warming of more than 3C and, for that reason, Labor cannot support that target.

“That has been a consistent position of ours since we first took advice about what Tony Abbott’s target would mean for climate change.”

Butler has argued that all of Labor’s policies need to be up for review after the election defeat in May, including the climate policies he developed over the last parliamentary term.

At a recent event in Canberra, Butler declared that after a federal election where Labor had its “backside handed to [it] by Fozzie Bear and Kermit the Frog – it’s time for some serious reflection”.

But on Wednesday he said Labor needed to continue championing climate policies that were consistent with the scientific advice.

“We will support medium-term targets that are consistent with the Paris agreement and based on the best available advice we can get,” Butler said. “Labor’s position [prior to the election] was based on advice from the Climate Change Authority, the body set up by the parliament to advise on these things. The government’s target was dreamed up by Tony Abbott.”

Senior Labor players are jostling for position ahead of a review spearheaded by Jay Weatherill and Craig Emerson to establish what went wrong during the election and in the lead-up to the contest.

This week, the former Labor leader Bill Shorten accepted a “collective” responsibility for the defeat and pointed to Labor’s franking credits policy as a particular problem.

Despite Butler’s efforts to hold the line, there is a view within the New South Wales right, the faction of which Fitzgibbon is a member, that Labor needs to seek a position of bipartisanship with the government to build support in regional NSW and Queensland, which swung to the Coalition in May.

Soon after the election loss, another member of the NSW right, Tony Burke, suggested Labor should radically overhaul its election policy offering but not wind back the level of ambition.