Opposition Leader Tony Abbott has agreed to give Labor MP Craig Thomson a parliamentary "pair" to attend the birth of his second child.

Yesterday Mr Abbott played hardball over the carbon tax debate, affirming the Coalition's refusal to grant pairs to Labor MPs for anything but the most extraordinary of circumstances.

Visiting Mr Thomson's NSW central coast electorate of Dobell yesterday, Mr Abbott was asked whether that could be relaxed for Mr Thomson to attend the birth of his child - an event which could fall during the protracted carbon tax debate.



"We have made it crystal clear that only in the most extraordinary circumstances will pairs be offered for the carbon tax vote," Mr Abbott told reporters.



"This is by far the most important vote that the Australian Parliament will take in the current term of Parliament and the first duty of members of Parliament is to be in the Parliament when critical votes are taken."

Government frontbencher Anthony Albanese said today that Mr Abbott's decision to grant Mr Thomson a pair to attend the birth of his child was a sign Mr Abbott had bowed to public pressure.

"Tony Abbott has been dragged kicking and screaming towards decency," he said.