An Egyptian court is about to hand down its verdict on Australian reporter Peter Greste, accused of supporting the former PM’s Muslim Brotherhood.

The family of Australian journalist Peter Greste says the prospect of him spending 15 years in an Egyptian jail is unthinkable.

Greste, who’s already been in jail for six months, will on Monday learn his fate for allegedly spreading false news and supporting former prime minister Mohamed Morsi’s Muslim Brotherhood.

An Egyptian court is due to deliver its verdict for Greste, two other reporters working for Qatar-based Al Jazeera English news network, and 17 other co-defendants.

Prosecutors have demanded the maximum penalty of 15-to-25 years in jail for all defendants.

Greste’s two brothers will be in court for Monday’s ruling, and say the family has been through agony since he was arrested in December.

“It’s unthinkable for us to expect anything other than an acquittal,” Mike Greste has told the ABC.

“All our lives have basically been put on hold for the last six months while we try to concentrate our efforts on securing Peter’s release and supporting him as best we can.”

He says prosecutors have offered no evidence to support the charges against his brother.

“Videos that had absolutely nothing to do with Egypt were shown in court, photographs of my parents, songs. The list goes on,” Mr Greste says.

Foreign Affairs Minister Julie Bishop has made last ditch appeals for the release of the journalist, including speaking directly with Egypt’s new foreign minister.

“I re-emphasised our concerns about Peter Greste and the fact that he’s been in detention since last year,” Ms Bishop told the ABC.

“I pointed out that he’s the only foreign journalist in these circumstances and I made the representations again that we wanted him home as soon as possible.”

She said Prime Minister Tony Abbott had also attempted to contact Egypt’s new president Abdel Fattah al-Sisi to lobby for the reporter’s release.

“So we are making representations at every level in the Egyptian government with a view to ensuring Peter Greste is home as soon as possible,” Ms Bishop said.

Last week, Mr Greste’s Brisbane-based parents also spoke of the toll the case had taken on their lives.

They said they were praying for an acquittal but were also holding talks with foreign affairs officials and planning strategies should worst-case scenarios eventuate.