A Cairo court has for the third time this month adjourned the retrial of two Al-Jazeera English journalists and six others over terrorism-related charges.

Al-Jazeera's Cairo bureau chief Mohamed Fahmy, a naturalised Canadian who has recently given up his Egyptian citizenship to win deportation, and Al-Jazeera producer Baher Mohamed have been charged with aiding a terrorist organisation, in reference to the Muslim Brotherhood. 

The pair were released on bail in February after more than a year in custody. A third Al-Jazeera journalist in the case, Australian Peter Greste, was deported days before their release.

Six other defendants, who are not Al-Jazeera employees, are being retried in the case on the same charges.

The court on Thursday said it would continue to hear the defence's arguments at its 25 June session.

The three were arrested in December 2013 and originally sentenced to between seven and ten years in jail on a raft of charges, including assisting a terror group and "spreading false news harmful to national security."

In January, a defence appeal was granted and a retrial set.

The case has sparked wide international outcry among journalists and rights groups.

Egyptian authorities accuse the Qatar-based Al-Jazeera of bias to the now-outlawed Muslim Brotherhood of deposed president Mohamed Morsi, allegations the network denies.

Fahmy has said he filed a lawsuit against Al-Jazeera accusing it of negligence in the handling his case.