WA Liberal David Johnston believes Tony Abbott is happy with his performance as Defence Minister, despite ongoing speculation he could soon lose his job in a Cabinet reshuffle.
The Prime Minister has played down talk he is poised to reshape his frontbench but says he encourages his team to be ambitious.
Speaking in Canberra yesterday, Senator Johnston said he enjoyed his job, though conceded he continued to serve in the position at Mr Abbott's whim.
"I enjoy my job and everyone wants my job because I deal with such great people," Senator Johnston said.
"I'm at the whim, the benefit, the consideration of the Prime Minister.
"Whatever he decides to do, I'm very happy."
In theory, Senator Johnston is the second-most powerful West Australian in Cabinet behind Foreign Affairs Minister and Deputy Liberal leader Julie Bishop.
But Finance Minister and WA Liberal Mathias Cormann now wields increasing power inside the Government.
The Government's recent Audit Report recommended Senator Cormann be formally appointed to the Government's most powerful internal body - the National Security Committee.
Immigration Minister Scott Morrison and Communications Minister Malcolm Turnbull are both said to be lead candidates to replace Senator Johnston in the Defence portfolio.
"No one has a job for life, this is politics, this is not some charitable institution," Senator Johnston said.
Asked if he was planning a reshuffle, Mr Abbott said all of his ministers should be doing their best at all times.
"We've been in Government for nine months, we've got a very big agenda before us, everyone is absolutely immersed in doing the right thing in his or her existing portfolio and that should continue," he said.
In a television interview on Thursday, Mr Turnbull refused to rule out the idea he still harboured ambitions to become prime minister.
Asked if he was worried that his ministers held leadership ambitions, Mr Abbott said he would be amazed if they did not.
"I think ambition is almost a prerequisite for going into Parliament," he said.
'No one has a job for life, this is politics, this is not some charitable institution.' " WA Liberal senator *David Johnston *