BEIRUT — The last Syrian rebels in the old city district of Homs held on to their positions Monday as they wait for a U.N.-supervised truce to go into effect that would give them safe passage to rebel-controlled towns in the provincial countryside.

Under the deal, which was announced Monday by the governor of Homs province, Talal al Barazi, the remaining rebels would be taken by bus to Talbisseh and Dar al Kabira, two towns north of Homs. The rebels also would identify where they planted booby traps in the old city. The deal is to take effect within 48 hours, “depending on the situation on the ground,” Barazi told Syrian state television.

It was unclear whether all of the groups in Homs, which include al-Qaida-linked militants from the Nusra Front, had agreed to the arrangement.

“I hope that things will go smoothly, in which case the initiative will be completed quickly,” Barazi said.

A rebel commander based in Lebanon who has helped with the negotiations said the deal foresees a rebel withdrawal over three days. He said about 2,000 rebel fighters and their families would be evacuated.

“We are in the process of working with the regime and the Red Crescent to arrange for a safe way for them to move and to show the regime where many of the booby traps and IEDs are set,” said the commander, Abu Omar al Homsi.

Unexploded ordnance will be a major hazard once the evacuation is complete.