Both the Prime Minister and Opposition Leader Tony Abbott have nominated the economy as their main battleground for 2012, as MPs returned to Parliament for the first sitting day of the year yesterday.

Mr Abbott, buoyed by recent opinion polls showing the opposition retains an election-winning lead, told colleagues at the first Coalition party room meeting for the year they were on a ``mission for our country''.

``They (the government) say they want the focus to be on the economy,'' Mr Abbott said.

``If I can plagiarise, `Make my day','' he added, referencing the words of actor Clint Eastwood in the 1971 film Dirty Harry.

Ms Gillard told Parliament Labor had set the direction for the economy with policies to improve skills and training, put a price on carbon emissions and bring the budget back to surplus in 2012-13.

``This is the debate of 2012,'' Ms Gillard said.

``I am very happy to say to the leader of the opposition, `Bring it on'.''

Half an hour into question time, the Reserve Bank of Australia announced it had left the official cash rate at 4.25 per cent, surprising financial markets which had predicted a 25 point cut.

Treasurer Wayne Swan said the RBA had ``struck a balance between global uncertainty on the one hand and Australia's strong economic fundamentals on the other''.

Opposition treasury spokesman Joe Hockey said the decision showed the government was getting the economic direction wrong.

``The clear message from the Reserve Bank is that the economy is fragile - that just proves that now is not the time to introduce an economy-wide carbon tax,'' Mr Hockey said.