Sudan's military rulers cancelled a previously agreed upon civilian transition process and announced snap elections after a deadly attack on peaceful protesters on Monday.
The opposition leaders were released amidst domestic and international criticism of the government for failing to ensure fair and representative elections.
More than 3 million people have now fled their homes due to the unrest in Sudan, either displaced within the country or have escaped abroad, the International Organization for Migration has said.
The leader of the Rapid Support Forces has unilaterally announced a truce over the course of Eid al-Adha, while his forces consolidate their power in Khartoum and violence spread to Blue Nile state.
In-depth: Amid a flurry of mediation offers by regional and international parties, a US-Saudi initiative is at the forefront of efforts to end the fighting, having engaged both warring sides and proposing a three-stage solution to restore calm.
Political parties and civil society groups have slammed Sudan's interim government for saying it would be 'moving forward' with the normalisation of ties with Israel.