Sudanese protest leaders are expected to unveil on Sunday a civilian council that they want to take power from the army rulers, who have resisted calls to step down despite mass demonstrations.
Thousands of protesters gathered outside the army headquarters in central Khartoum ahead of the announcement, an AFP correspondent reported, a day after the two sides pledged to hold more talks.
On Friday the Sudanese Professionals Association (SPA), which was at the forefront of the protest campaign that toppled longtime president Omar al-Bashir this month, said it would announce the civilian council at 1700 GMT.
It has invited foreign diplomats and journalists to attend the event at the rally site.
"We are waiting for the announcement today," Romaysaa Omar, one of the protesters, told AFP.
"All Sudanese people are in favour of the council to be announced by the SPA."
Whistling and waving Sudanese flags, dozens of demonstrators were sitting on a bridge at the site, banging stones against metal in rhythmical beats.
"We will stay at the site until all our demands are met," said Al-Baraa Yousef, another demonstrator.
On Saturday protest leaders and the military rulers held talks about a power handover and agreed to continue discussions.
"We clarified our main demand, which is the transfer of power to civilian authorities," Siddiq Yousef, a senior member of the Alliance for Freedom and Change, the umbrella group leading the protest movement, told state television after Saturday's talks ended.
"We agreed to continue negotiations to reach a solution that satisfies both the sides, so that the transfer of power will happen in a peaceful way."
'Want a timetable'
Yousef did not confirm whether protest leaders will go ahead with their planned unveiling of a ruling civilian council on Sunday.
But another senior leader of the movement told AFP on Saturday that it was possible it would be delayed.
"If they (the military council) are willing to negotiate, then there is a chance that tomorrow's (Sunday's) announcement could be postponed," Ahmed al-Rabia said.
Since Bashir was ousted on April 11 by the army in response to months of mass street protests, the military rulers have resisted calls to transfer power to a civilian body.
"What we want from them is a timetable to hand over power, so things don't drag on," said Rabia.
He said mounting pressure from the street and from the international community was expected to make the military council cede power in "two to three weeks".
"We are done with the easy part (toppling Bashir). We want to remove the entire regime," said Rabia.
Protest leaders say the civilian council would form a transitional government to rule Sudan for a four-year term, followed by elections.
"All we hope for is to be ruled by civilians and get rid of the military rule," said protester Ehsan Abdallah.
Many demonstrators expressed similar views as they sang, danced and chanted revolutionary songs and slogans outside the army headquarters late on Saturday.
The military council has made some concessions to the protesters by agreeing to demands such as detaining Bashir and releasing many political prisoners and demonstrators.
Prominent Sudanese journalist Khalid Tijani said the protest leaders were in a "tough situation" over finalising the civilian council.
"If they are not ready with the names, it will send a negative signal, and this will not be to the benefit of the revolution," said Tijani, editor of economic weekly Elaff.
Calls to hand over power to a civilian body have also come from the African Union (AU) and the United States.
On April 15, the 55-member AU threatened to suspend Sudan's membership by the end of the month if the military council failed to move to civilian rule.
On Saturday, AU chief Moussa Faki visited Khartoum and held talks with the military council and some opposition figures, but no details were available.
Washington's short-term goal is to "get the military folks out of centre-stage," a senior US official said on condition of anonymity earlier this week.
The official called for transitional authorities to prepare the way for "a truly democratic government that will reflect the will of the Sudanese people".