After 400 days in a Cairo prison, Al-Jazeera journalist Peter Greste was released from jail and will return home to Australia.

Greste was jailed with two other Al-Jazeera journalists: Baher Mohamed, a producer, and Mohamed Fahmy, the channel's Cairo bureau chief.

Mohamed and Fahmy still remain in prison.

Greste, Mohamed and Fahmy were arrested in December 2013.

The three journalists were falsely accused of spreading false news to help a terrorist organization. They were accused of collaborating with the banned Muslim Brotherhood after President Mohamed Morsi's overthrow by the military in 2013.

Their original sentence had them serving seven to 10 years in jail. Egypt's Court of Cassation overturned the sentences and ordered a retrial on Jan. 1.

Al-Jazeera tweeted they welcomed the news of Greste's release, while demanding the release of Fahmy and Mohamed.

The release of Greste comes after a long public campaign to free the prisoners.

In his first interview with Al-Jazeera, Greste called on Egyptian officials to release his fellow colleagues.

"I feel incredible angst about my colleagues, leaving them behind," Greste said on Monday.

"Amidst all this relief, I still feel a sense of concern and worry. If it's appropriate for me to be free, it's right for all of them to be freed."

According to Greste, the release was completely unexpected.

"I wasn't expecting [to be released] at all, I woke up thinking of the campaign ahead of us," Greste said. "I went for a run and the prison warden called me over and told me it's time to pack your stuff. He told me the embassy is coming."

The Egyptian Interior Ministry confirmed Greste's release with a statement, saying it had been "decided to extradite Australian journalist Peter Greste ... to his country today, Feb. 1 ... after the cabinet's approval, in enforcement of the Presidential Decree no. 140 for the year 2014 regarding the rulings on extraditing defendants and deporting the convicts."