Just who's the more senior minister? Is it Defence Minister Marise Payne or Defence Industry Minister Christopher Pyne?
The federal government hasn't spelled it out and it became no clearer on Wednesday during a Senate estimates committee hearing on defence.
Senator Payne noted Mr Pyne had been in cabinet longer, but she regarded them to be of equal rank. "It is not a matter of seniority. We are both members of cabinet," she said.
"Are you the senior minister in this portfolio?" asked Labor frontbencher Kim Carr.
Senator Payne said Mr Pyne was Leader of the House which gave him a particular role in the leadership group.
So, he is the senior minister, Senator Carr replied.
Senator Payne said she didn't see it in those terms.
"No, he is not. We are both cabinet ministers," she said.
Defence department secretary Dennis Richardson, a long-time and very senior public servant, couldn't shed much light on the issue.
"It is very simple - minister for defence, minister for defence industry, I know what they're responsible for," he said.
Mr Richardson said Senator Payne was a member of the national security committee of cabinet, the government's peak decision-making body for security, and had overall responsibility for defence policy and the defence budget.
The Department of Prime Minister and Cabinet gave him no direction on who was the senior minister.
"It's simply not been relevant to me. I know who's responsible for what," he said.
