CAIRO: Two Al-Jazeera journalists will face a retrial Thursday for allegedly supporting the banned Muslim Brotherhood despite the global outcry over their continued detention.

Mohammad Fahmy, who is Canadian and whose family hoped he would be deported before the trial, and Egyptian Baher Mohammad will appear before the court in Cairo after their Australian colleague Peter Greste was freed and sent home earlier this month.

The three journalists had been sentenced to up to 10 years in prison but an appeals court ordered a retrial saying the prosecution had failed to prove its case.

The case has been a major source of embarrassment for President Abdel Fatah al-Sisi as he seeks to shore up international support following a widely condemned crackdown on the opposition.

Sisi passed a law by decree last year allowing foreigners to be deported to their home countries to stand trial or serve out their sentences.

Shortly before the start of the retrial, Fahmy's fiancee Marwa Omara said she was disappointed that - unlike Greste - Fahmy had not yet benefited from the decree.

"We had assurances from the Canadian government and Egyptian officials that Mohammad was supposed to be out last Tuesday," Omara told AFP.

"I quit my job and packed my bags."

Fahmy dropped his Egyptian citizenship to benefit from the law and Canada last week said his release was "imminent."

"We are in shock and we feel that the Canadian government has failed in getting Mohammad out," Omara said.

The Canadian ambassador was inside the courtroom before the start of the trial.

Greste said his thoughts were with his colleagues ahead of the trial.

"Strange feeling to watch my cell mates and brothers Fahmy and Baher in court from the outside. My heart is in the cage with them," he wrote on Twitter.

Mohammad has only Egyptian citizenship so will be unable to benefit from the law.

The three journalists of Qatar-based Al-Jazeera English were arrested in December 2013 and charged with spreading false news about Egypt and supporting the Muslim Brotherhood.

Their arrests and continued detentions sparked widespread condemnation and calls for their release led by Washington and the United Nations.

The retrial was ordered after Egypt's Court of Cassation ruled in January that the lower court "lacked evidence to support its ruling" in the original verdict.

"The criminal court was hasty in pronouncing its verdict," it said.

"The court did not wait for medical and legal reports which it had requested after several defendants spoke of being under physical and moral pressure" to make confessions, the appeals court said.

The journalists were among 20 defendants initially tried by the lower court.

Of the rest, 12 were Egyptians found guilty of belonging to a "terrorist organisation."

Two defendants were acquitted, while the other three - also foreigners - were convicted in absentia.

The journalists' initial trial came against the backdrop of strained ties between Egypt and Qatar, which supported ousted president Mohammad Morsi.

The Islamist leader was toppled by then army chief Sisi in July 2013, before Sisi was himself elected president.

While Fahmy may still be deported - although that appears less likely once the trial starts - Mohammad's only hope is for an acquittal.

Sisi's office has said the president will not consider a pardon before the courts have finished their work.

Mohammad's wife Jihan Rashid said the family is "paying the price for being Egyptian."