Senator Fielding wrote to Mr Turnbull after a newspaper survey revealed most Liberal backbenchers opposed their leader's position of negotiating amendments with the Government.

Senator Fielding said the Coalition "should not capitulate to the Government's demands simply because it is afraid of giving … a double dissolution trigger". A decision to introduce a scheme to Australia before the rest of the world would be "economic suicide", he said.

His intervention came as confusion emerged in Coalition ranks over whether the joint party room had - when in government - approved legislation for the first step towards implementing such a scheme. An emissions scheme was a Howard government election policy.