Malcolm Turnbull has given an insight into his dealings with Donald Trump - and it involves a steel box.
The prime minister was speaking about the US president after he returned to Australia from the G20 Leaders summit in Germany.
"All of my dealings with him have been very frank, very informal. He's a businessman," Mr Turnbull told Seven Network on Friday.
"We had a very good discussion in his SCIF (secure communications information facility)."
Mr Turnbull described the room as being like a large steel broom cupboard, akin to Maxwell Smart's Cone of Silence in the American television series Get Smart.
"It is like a small, steel room and we had a very informal meeting with the president, myself, President Macron of France, (British prime minister) Theresa May, (Finance Minister) Mathias Cormann," he said.
"We went through a whole range of issues, some trade issues."
Mr Turnbull said while he might not always agree with President Trump, he was easy to deal with because you know where you stand.