BEIRUT — Syria’s military began withdrawing from a major artery to Aleppo late Thursday as the U.N. envoy accused President Bashar Assad’s government of obstructing aid access to the contested city.

A monitoring group reported three civilian fatalities, the first since the U.S.-Russian-brokered cease-fire took effect three days ago.

Meanwhile, Russia was expected to deploy its forces along Aleppo’s Castello Road to ensure safe passage for humanitarian convoys to the city’s opposition-held quarters. It would be the most overt participation by Russian ground forces in the Syrian war, underscoring Moscow’s position as power broker in the conflict. Russia intervened with its air force on the side of the Assad government last year, turning the tide of the war in his favor.

As part of the truce deal, the rebels and the Syrian government are supposed to agree to the deployment of a security force to protect checkpoints along the route to Aleppo to ensure aid delivery to the city’s opposition sector, which has been besieged by Russian-backed government forces since July. The U.N. estimates about a quarter million people are trapped inside.

However, the U.N. envoy to Syria, Staffan de Mistura, said despite the dramatic drop in violence since the cease-fire took effect on Monday, the humanitarian aid flow that was supposed to follow had not materialized.

Speaking in Geneva, de Mistura blamed Assad’s government for the delay.

He said the Syrian government had not provided the necessary “facilitation letters,” or permits, to allow the aid convoys to reach opposition areas, disappointing even Russia, the Syrian president’s key backer.

De Mistura said 40 aid trucks were ready to move and the U.N. would prioritize delivery to the embattled rebel-held eastern neighborhoods of Aleppo.

“That is what makes a difference for the people, apart from seeing no more bombs or mortar shelling taking place,” he said of the aid deliveries that are supposed to be part of the truce deal.

“It is particularly regrettable. … These are days which we should have used for convoys to move … because there is no fighting,” he said.

Jan Egeland, the top humanitarian aid official in de Mistura’s office, said the U.N. could reach its target areas in the country within a “few days” once it received authorization.

“Our appeal is the following,” Egeland said. “Can well-fed, grown men please stop putting political, bureaucratic and procedural roadblocks in the way of brave humanitarian workers who are willing and able to go to serve women, children and wounded civilians in besieged and cross-fire areas?”

Activists reported the cease-fire was holding despite some violations, though the Syrian Observatory for Human Rights monitoring group warned the rate of violations had escalated and three civilians were killed, including two children.

The Britain-based Observatory, which relies on a network of activists on the ground, said one girl was killed when missiles fired by rebels hit a village in the southern province of Quneitra. Another child died of wounds sustained from a sniper fire in al-Masharfeh, a government-held neighborhood in Aleppo city. The third casualty, according to the Observatory, was a civilian who also died by sniper fire in the rebel-held part of Aleppo.

Russia’s military announced Thursday evening that Syrian government forces had begun withdrawing from the route to Aleppo, though the Pentagon said it had no indication of a withdrawal. The Syrian Observatory for Human Rights monitoring group also reported the government was leaving the area.

The rebels were expected to follow suit, according to U.N. and government officials, though there was no indication they had done so late Thursday. The withdrawals will make way for the Syrian Arab Red Crescent to establish checkpoints on the road and direct aid convoys in.

It was not immediately clear who would secure the route, though the Syrian Observatory for Human Rights monitoring group reported Russian forces were taking up positions. The Russian military could not immediately be reached for confirmation.

The text of the cease-fire agreement has not been released and Russia said it was being kept private at the request of the United States. Moscow wants the U.N. Security Council to endorse the agreement when it meets next Wednesday, according to Ambassador Vitaly Churkin.

Russia and American officials have said the agreement is intended to set the stage for peace talks to resolve the Syrian war, now in its sixth year.

Aleppo has been the center of fighting in recent months and Syrian government forces and their allies launched a wide offensive earlier this month, capturing several areas south of the city and putting eastern rebel-held neighborhoods under siege for the second time in two months.

Over 2,000 people were killed in 40 days of fighting in Aleppo until the cease-fire went into effect Monday. The dead include 700 civilians, among them 160 children, according to the Syrian Observatory for Human Rights.

“No aid has arrived in Aleppo. The regime is refusing to allow aid into Aleppo,” said an activist based in the city, Baraa al-Halaby.

Syria’s state news agency SANA said opposition fighters opened fire at a location along the Castello Road that was being prepared for Red Crescent representatives, and two people guarding the area were wounded.

SANA also reported violations in the northwestern village of Foua, saying insurgent sniper fire wounded a Syrian boy. It said three shells were also fired at the government-held southern village of Hadar.

Meanwhile, in the eastern province of Deir el-Zour, clashes and shelling over the past 24 hours between government forces and the Islamic State group in the provincial capital, also called Deir el-Zour, killed at least three people, including a child, according to activists and state media.

Elsewhere in the province, an airstrike on the IS-held town of Mayadeen killed at least nine people and wounded dozens, according to opposition activists and Deir el-Zour 24, an activist collective. The Observatory said the airstrike killed 23 people. It wasn’t known who carried out the attack.

The truce does not include the Islamic State group, and the U.S.-led coalition, Russia and Syrian government forces have all been carrying out strikes against the extremist group.

Also not included in the truce is the al-Qaida affiliate in Syria, Fatah al-Sham, formerly known as the Nusra Front.


Keaten contributed from Geneva. Associated Press writer Bassem Mroue in Beirut contributed to this report.