Sudanese protesters on Sunday demanded the country's military rulers "immediately" hand power over to a civilian government that should then bring ousted leader Omar al-Bashir to justice.

Thousands remained encamped outside Khartoum's army headquarters to keep up pressure on a military council that took power after ousting Bashir on Thursday.

On Sunday the organisation which spearheaded the protests against Bashir, the Sudanese Professionals Association, called on the military council "to immediately transfer power to a civilian government".

The SPA also demanded the next "transitional government and the armed forces to bring Bashir and all the chiefs of the National Intelligence and Security Service (NISS)... to justice".

"The Sudanese Professionals Association calls on its supporters to continue with the sit-in until the revolution achieves its demands," it added.

Earlier the military council met with political parties and urged them to agree on an "independent figure" to be the country's prime minister, an AFP correspondent present at the meeting said.

"We want to set up a civilian state based on freedom, justice and democracy," a council member, Lieutenant General Yasser al-Ata, told several political parties, urging them to agree on the figures to sit in civilian government.

The protesters have insisted civilian representatives must join the military council.