Thousands of pro-democracy activists took to the streets in Sudan's capital to reject the agreement signed by military and civilian leaders on December 5, which critics have dismissed as vague.
"We will not accept anything other than a civilian government," said protestor Samira Hassan.
The protesters chanted, "You will not rule us with this deal," according to an AFP correspondent.
Others called on the military to go "back to the barracks".
Security forces later fired tear gas to disperse the crowd, the AFP correspondents said.
Monday's demonstration coincided with the fourth anniversary of the outbreak of months-long mass protests that ousted long-time autocrat Omar al-Bashir in April 2019.
Bashir's three-decade rule was followed by a short-lived transition to civilian rule, upended in October 2021 when army chief Abdel Fattah al-Burhan led a coup, deepening Sudan's political and economic turmoil.
Sudan has been rocked by near-weekly protests since Burhan's coup.
The deal between military leaders and multiple civilian factions was the first component of a planned two-phase political process, but critics say it falls short on specifics and timelines.
While opponents at home eyed it with scepticism, the deal drew some international acclaim.
"I hope that the political process will realise the demands & aspirations of the Sudanese men & women who took to the streets 4 years ago," UN special representative Volker Perthes tweeted on Monday.
Sudan's Finance Minister Gibril Ibrahim, a former rebel leader who did not sign the agreement, called it "exclusionary".
"Today we observe the fourth anniversary of the glorious December revolution which did not achieve its goals," he said Monday on Twitter.
"The country is in dire need of a national consensus that does not exclude anyone."
Sudanese authorities declared Monday a public holiday and security forces had sealed off bridges leading to the capital.
Roads leading to the army headquarters in Khartoum -- the site of a mass anti-Bashir encampment in 2019 -- were also closed, an AFP correspondent said.
The protesters waved Sudanese flags and carried posters with the images of people killed during anti-coup demonstrations since October 2021.
At least 122 people have been killed and thousands wounded in the crackdown, according to pro-democracy medics.
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