Decision comes days before major constitutional referendum
The trial of Egypt's ousted Islamist president Mohammed Morsi on charges of inciting the murder of protesters was adjourned on 8 January until 1 February.
Morsi faces charges of inciting violence including the killing of about a dozen protesters outside the presidential palace in December 2012, following a decree that gave him sweeping powers.
Authorities said that heavy fog prevented the helicopter carrying Morsi from his high security prison in Borg el-Arab, just outside of the Mediterranean city of Alexandria, to the court in the suburbs of Cairo.
However his Muslim Brotherhood movement has accused the military-backed interim government of attempting to keep Morsi out of the public eye ahead of a key referendum on a new constitution, on 14-15 January.
The nationwide referendum involves rewriting the charter drafted largely by Islamists and overseen by Morsi prior to his popularly-backed ousting by the military on 3 July. Around 680,000 Egyptians living abroad began voting on the new charter on 9 January.
If a strong majority of Egyptians support the referendum and there is a large turnout the interim government would gain significant legitimacy, allowing it to continue its transition plan for parliamentary and presidential elections later this year.
Since Morsi's overthrow there has been widespread political unrest and violence in Egypt while the interim government continues its crackdown on Muslim Brotherhood leaders, its supporters and assets. In December it formally declared the Brotherhood a terrorist organisation.