More than a dozen of Australia's largest companies including BHP Billiton, Westpac and Origin Energy, have signed up to take long-term action on climate change.
The firms have joined more than 250 global corporations, boasting more than $US5.6 trillion ($7.7 trillion) in annual turnover, that have agreed on steps such as putting a price on carbon and buying 100 per cent of their electricity from renewable sources.
The pledges by companies, which also include ANZ, Commonwealth Bank, AGL, Infigen??? and Brambles, come just weeks before delegates from almost 200 nations meet in Paris to negotiate a global climate treaty aimed at keeping temperature increases to within 2 degrees of pre-industrial levels. 
It comes as Commonwealth Bank is tipped to make an announcement on Thursday morning about its own policies on climate change.Fairfax Media understands the bank has been in talks with environment groups about committing to the global goal of limiting climate change to 2 degrees of warming. However, it is unlikely the bank will be looking at policies to reduce its investment in fossil fuel projects.Instead, it will look at other proposals that will help the transition to a low carbon economy, such as increasing its focus on renewable energy and looking at ways carbon intensive projects can lower their emissions. CBA declined to comment.
Prime Minister Malcolm Turnbull is due to speak at the first day of the Paris summit, on   November 30. Australia has pledged to cut global emissions about 19 per cent on 2000 levels by 2030, which also translates to a 26-28 per cent cut on 2005 emissions.
Australian states are sending various delegations, with Terry Bailey, the chief executive of the Office of Environment and Heritage expected to be the highest-ranked NSW government delegate.
"Over the course of the last six to 12 months, we've seen a significant shift in attitudes, policies and actions of major companies on climate change - both in Australia and globally," James Day, director of the CDP group in Australia, said.
The 13 Australian signatories to the We Mean Business group will be unveiled at a Climate Leadership Summit to be held in Sydney on Thursday.
Origin Energy, along with Bank Australia, were the only ones of the group to commit to all seven goals, including putting an internal price on carbon and adopting a science-based emissions-reduction goal.
"Energy production is responsible for two-thirds of global carbon emissions, which means energy companies must play a central role in delivering the solutions that will help to reduce emissions globally," Gordon Cairns, Origin Chairman said.
The energy firm, whose fossil-fuel portfolio includes mostly gas-fired power plants and one coal-fired one, plans to work with external parties to set the emissions targets. " This is the most material one for us [of the seven]", an Origin spokeswoman said.
The 100 per cent renewable energy pledge  covered only the company's office operations, not its power plants, she said.
Businesses are expected to play a large part in future climate action, particularly if long-term goals - such as cutting emissions by as much as 80 per cent by 2050  - get broad backing by governments.
Dermot O'Gorman???, head of WWF-Australia, said company backing for climate action could also nudge nations - including Australia - to do more.
"This growing momentum opens the door for governments to play their part at the upcoming UN climate change meeting in Paris," Mr O'Gorman said.
With Lisa Cox