Jailed Australian journalist Peter Greste has praised the international response to his case as he prepares to face an Egyptian court for the seventh time on charges of terrorism.

Greste is accused of spreading false news and having links with the outlawed Muslim Brotherhood movement of ousted president Mohamed Morsi.

His Al Jazeera colleagues - Egyptian-Canadian Mohamed Fahmy and producer Baher Mohamed - and their Egyptian collaborators are also accused.

Greste's parents, Lois and Juris, today read a new statement from their son, who has now been in a Cairo prison for more than 120 days.

Greste appears in court tomorrow, which is World Press Freedom Day.

In his latest message, Greste acknowledges the international "outpouring of support" which he says is "unprecedented in the struggle to protect press freedom".

"If by arresting us, the (Egyptian) government sought to send a message to journalists both foreign and local working here, then the campaign for our release has sent an unequivocal response," the statement said.

"It is one that is being heard everywhere.

"We are confident that in time and hopefully soon all three of us will be acquitted and released."

Greste's parents say they will keep fighting for his release.

"We are not leaving any stone, any little pebble unturned because as parents we just cannot rest until Peter is out and exonerated," Mr Greste said.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 5 minutes 19 seconds 5 m Al Jazeera English MD Al Anstey speaks about the case Download 2.4 MB

He says this latest message from his son is reassuring.

"We are immensely assured that Peter is managing to remain mentally and psychologically stable even though the circumstances are difficult," he said.

Lois and Juris Greste say Peter remains in a good state of mind. ( ABC News: Nic MacBean )

When asked whether the Federal Government was doing enough to secure Greste's release, his father replied: "In one sense you could wonder, have they? Because he is still behind bars".

"And yet our feeling, our sentiment is that our government has worked hard and we certainly believe that all is being done to secure Peter and his colleagues' release," he said.

But Greste's parents are not getting their hopes up about tomorrow's court appearance.

"We may be considered slow learners ... but one thing that we have learnt is not to conjecture or speculate or expect anything in particular," Mr Greste said.

"We literally work day by day."