The foreign correspondent, who spent 400 days in Tora prison in Cairo, wants to thank the politicians, Department of Foreign Affairs and Trade staff and diplomats who secured his release.

And he wants to thank the journalists who kept his story on the front pages until Egyptian authorities finally allowed him to walk free on February 1, 2015.

Greste made international headlines in December 2013 when he and two colleagues, Mohamed Fahmy and Baher Mohamed, were dramatically arrested while working for Al Jazeera English in Cairo.

The three men were charged with consorting with the banned group Muslim Brotherhood and, in June 2014, were sentenced to seven years' jail.

The case attracted international attention, with US President Barack Obama and British Prime Minister David Cameron both speaking out in support of the incarcerated men.

Prime Minister Tony Abbott and Foreign Minister Julie Bishop came under intense pressure to secure Sydney-born Greste's freedom.

"I know there has been criticism of the way it was handled, but, from our point of view, it was handled astutely. And it needed to be," Greste said on Wednesday, at the start of his three-day Canberra visit. "There was a degree of diplomatic restraint that recognised all the political subtleties that needed to be taken account of.

"And, in any event, whatever they did eventually worked," said Greste's mother, Lois.

She and Greste's father, Juris, lobbied tirelessly on their son's behalf.

Now, the family is on tenterhooks, awaiting news overnight from the Egyptian court that is continuing hearings in the case against Fahmy and Mohamed.

The Greste family – including Peter's two younger brothers, Andrew and Michael – attended a special parliamentary reception on Wednesday evening in which they were able to pass on their thanks personally to Mr Abbott, Ms Bishop, cabinet members and key DFAT staff.

On Thursday, Greste will deliver a sold-out National Press Club address in which he will speak of 400 days in jail, two weeks in solitary confinement, his torment at having to leave his two colleagues behind and the importance of a free press.

He said it "sits a little oddly" with him that he has become a celebrity journalist.

"I have forged a career reporting on the news, not being at the centre of it," the former BBC and CNN journalist said.

But he and his parents believe the platform Greste has been given to promote the importance of press freedom is too important to pass up.

"Let's not forget there are other journalists in prison as we speak," he said.

In the coming weeks, Greste will be preparing for World Press Freedom Day on May 3 in Riga, Latvia – a location that elicits undisguised delight from his Latvian father.

He has appointments in Washington and New York, and is negotiating a return to special journalism projects in the future.

Meanwhile, he intends "noticing the little things, the sunlight, the clouds, the stars – all of which sounds a little romantic, but when you have spent 400 days in a box, they take on a whole new importance and joy".