Australian journalist Peter Greste has vowed to fight the "outrageous" three year sentences handed to him and two Al Jazeera colleagues in an Egyptian court.
And any efforts by Mr Greste to contest the conviction will be supported by the federal government, says Foreign Minister Julie Bishop.
Ms Bishop said in a statement on Saturday, shortly after the verdict was delivered, she was "dismayed" by the trial's outcome.
She said she had spoken with Mr Greste and that she would "continue to pursue all diplomatic avenues with (her) Egyptian counterpart to clear his name".
Mr Greste was convicted in absentia but his colleagues, Canadian national Mohammed Fahmy and Egyptian producer Baher Mohammed, were taken from the court in Cairo immediately after they were sentenced.
Judge Hassan Farid said in his ruling he had sentenced the men to prison because they had not registered with the country's journalist syndicate.
He also said the men brought in equipment without security officials' approval, had broadcast "false news" on Al Jazeera and used a hotel as a broadcasting point without permission.
Convicting three journalists as terrorists without any evidence is "outrageous" and was purely a political move, Mr Greste told Al Jazeera.
In December 2013, Egyptian security forces raided the up-market hotel suite being used by Al Jazeera to report from Egypt.
Mr Greste, Mr Fahmy and Mr Mohammed were subsequently charged with airing falsified footage intended to damage national security and with being part of ousted president Mohammed Morsi's Muslim Brotherhood, which is considered a terrorist organisation.
The three men were convicted on June 23, 2014, with Mr Greste and Mr Fahmy sentenced to seven years in prison and Mr Mohammed to 10 years.
Egypt's Court of Cassation, the country's highest appeals court, later ordered their retrial, saying the initial proceedings were marred by violations of the defendants' rights.
Egypt deported Mr Greste in February even though he remained charged in the case. Mr Fahmy and Mr Mohammed were later released on bail.
In a statement following Saturday's verdict, Al Jazeera said the sentences were a "deliberate attack on press freedom" and that it would not rest until its staff "are freed".
In a joint statement, Labor leader Bill Shorten and opposition foreign affairs spokeswoman Tanya Plibersek said the sentence was "unjust" and that "journalists shouldn't be put on trial or locked up for doing their job anywhere in the world".
Mr Greste said he had been in contact with his lawyer but would not be appealing the sentence as that would require him to return to Egypt.
"We will explore any other legal avenues that we have open to us," he said.
Mr Greste has called for governments and diplomats across the world to "make it clear to Egypt that it cannot make these kinds of judgments".