The federal coalition will change its policy on climate change as the inevitable result of changing international factors, treasury spokesman Malcolm Turnbull says.
The coalition has been split over emissions trading and is set to thrash out the issue at meetings in Canberra this week.
The main point of contention is whether Australia should implement a genuine emissions trading scheme if heavy polluters do not agree to take action first.
"Inevitably our policy will change," Mr Turnbull told the Nine Network.
"Political parties' policies are a living thing, they change from time to time."
He said changing international factors, including a new US government, would see the coalition take a fresh climate policy to the next election.
Mr Turnbull denied senior Liberals had taken different positions on emissions trading recently.
"We've all been singing off the same song sheet," he said.
Mr Turnbull reiterated his version of the Liberals' policy, which is that emissions trading should start by 2012 "in advance of, but in the expectation of" a global agreement on climate change.
Leader Brendan Nelson wants Australia to bring in genuine emissions trading only after other countries have agreed to act.
Mr Turnbull denied there was a difference of opinion.
"I have not been able to discern in anything Brendan Nelson has said publicly ... since he's been leader, or indeed that I've said publicly, any difference."
Asked if adopting Dr Nelson's policy would make the Liberals less green than they had been under John Howard, Mr Turnbull replied: "Well he wasn't known for being too green, that's for sure."
