An army tent was erected to accommodate the Prime Minister, and the Gulkula Knowledge Centre was converted to an administrative hub, where the nation's top public servant, Ian Watt, and many others will be based.

Now, the unprecedented has become the unimaginable: a prime minister making decisions on when deployment turns into military engagement and reacting to an unfolding international crisis in a surreal setting.

Mr Abbott made it plain on Sunday that his being in north-east Arnhem Land would not prevent him picking up the phone to Barack Obama and other world leaders as required.

"It is my intention to be in Arnhem Land for the week that I promised," he said in Darwin, en route to Nhulunbuy, at the northern tip of Arnhem Land. "But I will be in regular contact with Canberra. There are secure communications available to me in Arnhem Land that are, in fact, being provided by the Australian Defence Force."

Mr Abbott received a warm welcome to country on Sunday evening from the Yolngu people and one of the country's pre-eminent indigenous leaders, Galarrwuy Yunupingu, who has done as much as anyone to put the issue of constitutional recognition on the agenda.