Rapturous crowds filled the streets of Khartoum on Saturday as Sudan's generals and protest leaders signed a historic deal paving the way for civilian rule.

Thousands of cheering people gathered around the Friendship Hall next to the Nile, where the documents that will govern the country's 39-month transition were signed.

“This is the biggest celebration I have ever seen in my country. We have a new Sudan,” said Saba Mohammed, a veiled 37-year-old woman, waving a small plastic flag.

Minutes earlier, the deal had been signed by Mohamed Hamdan Daglo, deputy chief of the military council, and Ahmed al-Rabie, representing the Alliance for Freedom and Change protest umbrella.

Heads of state, prime ministers and dignitaries from several countries — including Ethiopia's Prime Minister Abiy Ahmed and Egypt's premier Mustafa Madbuli — attended the ceremony.

The constitutional declaration formalises the creation of a transition administration that will be guided by an 11-member sovereign council, comprised of six civilians and five military figures.

After brandishing a signed green book containing the transition documents, protest leader Mohamed Naji al-Assam called on the military council to work “together to establish a sustainable democracy.”

The agreement brought an end to nearly eight months of upheaval that saw masses mobilise against president Omar al-Bashir, who was ousted in April after 30 years in power.

Thousands of people had arrived on trains from Sudan's provinces to take part in the celebrations, which will include a huge gathering in Khartoum's main gardens.

“We hope Sudan can move forward now, we want to be proud of our country,” said Saida Khalifa as she got off the train after an all-night ride from Atbara, the town where the protests started in December last year.

“The guns must go silent now and we must pull the country out of this mess to gain peace and freedom,” she said.

New institutions

The celebrations looked set to last deep into the night as tens of thousands of people converged on the capital's main park, spilling out of honking cars and tuk tuks.

The composition of the civilian-majority transitional ruling council is to be announced on Sunday.

That follows the naming on Thursday of former senior UN official Abdalla Hamdok, a veteran economist, as transitional prime minister.

He is expected to focus on stabilising Sudan's economy, which has been in a tailspin since the oil-rich south seceded in 2011.

Economic woes triggered the initial protests in December.

At Khartoum's central market early Saturday, shoppers and stallholders interviewed by AFP all said they hoped a civilian government would help them put food on the table.

Residents old and young were eager to exercise their newfound freedom of expression.

“I'm 72 and for 30 years under Bashir, I had nothing to feel good about.

Now, thanks to God, I am starting to breathe,” said Ali Issa Abdel Momen, sitting in front of his modest selection of vegetables at the market.

But many Sudanese are already questioning the ability of the transitional institutions to rein in the military elite's powers during the three-year period leading to planned elections.

End of isolation?

The country of 40 million people will be ruled by the 11-member sovereign council and a government, which under the deal must be dominated by civilians.

However, the interior and defence ministers are to be chosen by military members of the council.

Observers have warned that the transitional government will have little leverage to counter any attempt by the military to roll back the uprising's achievements and seize back power.

When he walked out of the Friendship Hall after signing the declaration, the general seen as Sudan's new strongman, Mohamed Hamdan Daglo, was met with a hostile crowd.

Members of the paramilitary Rapid Support Forces he commands shielded him back to his car as the crowd saw him off, chanting “blood for blood”.

They were referring to the alleged role played by his men in the bloody crackdown on a June 3 sit-in that doctors say left at least 127 dead and 11 missing.

Security forces deployed across Khartoum Saturday for the biggest international event in years in Sudan, which had become something of a pariah country under Bashir's rule.

One of the most immediate diplomatic consequences of the compromise reached this month could be Sudan's return to the African Union, which suspended the country's membership in June.

Bashir, who took power in a 1989 coup and is wanted by the International Criminal Court on charges of genocide in the Darfur region, had been slated to appear in court Saturday on corruption charges.

But his trial has been postponed to an as yet undetermined date.