Questions are being raised about the future of Peter Costello, as rumours continue of a possible leadership tilt if he stays on in parliament.
The former treasurer is under pressure to make his intentions known following the resignation of another senior Howard-Government minister, Mark Vaile.
But Shadow Treasurer Malcolm Turnbull has told the ABC, whatever the decision, it is his to make, and his alone.
"This discussion is interesting, but in a way a bit pointless, this is a matter for Peter (Costello).
"Peter's got to make his own decision. I respect that and I respect his right to make that decision without being hectored or cajoled by his collegues on television."
Treasurer Wayne Swan has told Channel Ten anyone else considering retirement should do it now and it is up to the Opposition Leader to pull his backbench MP's into line.
"We've got all of those sitting round the back bench, like Peter Costello, thinking about going.
"Well they ought to all go at once and they ought to save the taxpayers some money.
"So it's about time Brendan Nelson put an end to this by-election farce that's going on."