In a speech to the Nationals' federal council in Canberra on the weekend, Mr Truss called for "direct intervention" to cut emissions, warning that the Government's plan to introduce an emissions trading scheme by 2010 would push up prices and force Australian industry overseas.

"Perhaps most serious of all is if Australia has a harsh emissions trading scheme and other countries do not, investment activity and industries will migrate with their jobs to non-participating nations," he said.

The comments serve to further cloud the Coalition's climate policies.

Opposition Leader Malcolm Turnbull wants an emissions trading scheme by 2012.

But it remains unclear whether the Coalition would proceed in the absence of international co-operation.