Hundreds of journalists have gathered in London to protest against the seven-year jail terms given to three al-Jazeera journalists in Egypt.
A court in Cairo found Australia's Peter Greste, Mohamed Fahmy and Baher Mohamed guilty of spreading false news.
The trio had denied the charges and are expected to appeal.
Egypt's President Abdul Fattah al-Sisi said on Tuesday he would not "interfere" with the judiciary which he described as independent.
Earlier, Australian FM Julie Bishop told the BBC Canberra would work with the Egyptian government to try to secure Mr Greste's release "as soon as possible".
"We support Egypt's transition to democracy, but that also includes freedom of speech and press."
Ms Bishop also ruled out imposing sanctions on Egypt, saying it was "not helpful at this stage".
The father of Mr Greste told reporters in Brisbane that the family was "devastated" and "shocked" by the verdict.
"This is a very dark time, not only for our family but for journalism generally," Juris Greste said, describing the ruling as a "slap in the face" to "all fair-minded people around the world".
"Journalism is not a crime, or you should all be behind bars,'' he added.
But Mr Greste's parents were reluctant to criticise the Egyptian judicial system, reports the BBC's Jon Donnison in Sydney, aware that might hinder the ongoing diplomatic efforts to put pressure on the Egyptian government.
Hopes are now pinned on the possibility of a pardon from Egyptian President Sisi, our correspondent says.
BBC staff were joined by colleagues from other news organisations in a one-minute silent protest outside New Broadcasting House in London.
The protest took place at 09:41 BST (08:41 GMT) - exactly 24 hours after the sentencing in Cairo on Monday.
"The case is unjust," the BBC's News Director James Harding told the gathering.
He added that journalists around the world "have to stand together" for reporters being imprisoned for simply doing their job.
Mr Harding added that journalists would be sending a letter to the Egyptian president, calling him to intervene.
The jail terms handed out to the three journalists accused of supporting Egypt's Muslim Brotherhood led to an international outcry.
The White House said that jailing journalists because their reporting did not fit the government "narrative" was "a blow to democratic progress in Egypt".
BBC Director of News James Harding said the BBC, alongside other news organisations, would be submitting a letter to the Egyptian president asking him to address "this injustice".
The BBC's Bethany Bell in Cairo says that while the case has been condemned around the world, it has been presented differently by the Egyptian media.
Al-Jazeera, which is based in Qatar, was banned from operating inside Egypt after being accused of broadcasting reports sympathetic to former President Mohammed Morsi and the Muslim Brotherhood. Al-Jazeera has consistently denied the allegations.
Human rights group Amnesty said the trial was a "vindictive farce" and part of the "ongoing row" between Egypt and Qatar, which backs the Muslim Brotherhood.
- Defendants included al-Jazeera's Cairo bureau chief, Mohamed Fahmy, who is Canadian-Egyptian, Egyptian producer Baher Mohamed and Australian correspondent Peter Greste
- They denied charges of spreading false news and supporting the Muslim Brotherhood
- The three men were seized in a raid at a Cairo hotel on 29 December and have been held at Cairo's Tora prison
- The court tried a total of 20 people, including nine al-Jazeera employees
Eleven defendants tried in absentia, including three foreign journalists, received 10-year sentences. Two of the journalists convicted in absentia are British.
In a statement, al-Jazeera English's managing director Al Anstey said the sentence "defies logic, sense, and any semblance of justice".