Stores and restaurants reopened on Wednesday in Khartoum, after Sudan's protest leaders chose to end the civil disobedience launched after the army's brutal crackdown.
Sudan's ruling military council Thursday for the first time admitted it had ordered the June 3 dispersal of a Khartoum protest sit-in that left dozens dead and hundreds wounded.
The visit comes after an Ethiopian envoy said the ruling Transitional Military Council and an alliance of protest and opposition groups had agreed to resume talks and the alliance suspended a three-day strike.
Sudan's ruling military council Thursday for the first time admitted it dispersed a Khartoum sit-in, which left dozens dead, as United States and African diplomats stepped up efforts for a solution to the country's political crisis.
Arman had arrived in Khartoum in late May to take part in talks with the military council that toppled longtime president Omar al-Bashir after months of protests against his 30-year-rule.
There was no immediate confirmation from the protesters or the Sudanese military on the resumption of talks.
Experts say the three key regional powers back the generals.
The protest movement itself said in a statement that it was calling on people "to resume work from Wednesday".
On 4 June, Burhan announces that all previous agreements with protest leaders on a transition are scrapped.
Jalab and Ardol were detained after meeting Ethiopian prime minister Abiy Ahmed in Khartoum on Friday for talks aimed at reviving negotiations between Sudan's rulers and protesters.
"The Military Council has made a decision to reinforce the presence of armed forces, RSF and other regular forces to help normal life return", the council member said, including the feared Rapid Support Forces, blamed by witnesses for the killings last week as a sit-in protest outside army headquarters was cleared.
The health ministry later acknowledges 61 deaths nationwide, 52 of them from "live ammunition" in Khartoum.
The US State Department nominated experienced Africa hand Donald Booth as a special envoy to Sudan on Wednesday, hoping he can help craft a "peaceful political solution" between the military rulers and groups seeking civilian rule.
"His appointment demonstrates that the United States has a firm commitment to the Sudanese people and efforts to advance a peaceful political solution", spokeswoman Morgan Ortagus said Wednesday.
The state-run SUNA news agency said Sudanese diplomat Elham Ibrahim had met with Nagy soon after his arrival.
Governments around the world, including the United States, have condemned that violence.
Protesters have demanded a swift transfer to civilian rule since the military seized control from Bashir and locked him up.