Clashes and air strikes shook the Syrian city of Aleppo, a monitor said Sunday, as heavy fighting resumed after the end of three-day truce declared by government ally Russia.
The unilateral truce ended without any evacuations by the UN, which had hoped to bring wounded civilians out of the rebel-held east and deliver aid after weeks of government bombardment and a three-month siege.
The Syrian Observatory for Human Rights reported heavy clashes overnight in several areas along the front line that divides the government-held west from the east.
The Britain-based monitor also reported the first air strikes since Moscow announced a temporary halt in the Syrian army\’s Russian-backed offensive to recapture the east of the city.
It said at least three people were wounded in artillery fire on the east of the city, while rebels fired a barrage of rockets and mortar shells on the government-held neighbourhood of Hamdaniyeh.
By Sunday morning, the city was quiet, but it was unclear if there would be any renewal of the truce, which Moscow and Damascus said was intended to allow civilians and rebels to leave the east.
The army had opened eight corridors from the east, but only a handful of civilians were reported to have crossed through a single passage, with the rest remaining deserted.
Russian officials and Syrian state media accused rebels of preventing people from leaving and using civilians as "human shields".
Nearly 500 people have been killed and more then 2,000 wounded since the Syrian army launched a September 22 operation to recapture eastern Aleppo.
The United Nations had hoped to use the "humanitarian pause" to evacuate seriously wounded people and possibly deliver aid.
But a UN official said Saturday the requisite security guarantees had once again not been received.
"You have various parties to the conflict and those with influence and they all have to be on the same page on this and they are not," said David Swanson, a spokesman for the UN humanitarian office.
The UN had drawn up a four-day plan that was to start with two days of medical evacuations to west Aleppo, rebel-held Idlib province, and Turkey, and continue with more evacuations as well as aid deliveries.
No aid has entered Aleppo since July 7 and UN chief Ban Ki-moon has warned food rations will run out by the end of the month.
The UN had asked Moscow to consider extending the pause until Monday evening, but there was no indication from Russia that it would.
Russia is a key ally of Syria\’s government and began a military intervention in support of President Bashar al-Assad last September.
Kremlin spokesman Dmitry Peskov said in an interview aired Saturday that the intervention was meant to "liberate" Syria and keep Assad in power.
"Either Assad is in Damascus, or Al-Nusra is," he said, referring to former Al-Qaeda affiliate the Fateh al-Sham Front. "There is no third option here."
In the hours before the truce expired, the Observatory said both sides appeared to be reinforcing their positions in preparation for renewed clashes.
"The regime and the rebels are both bolstering their forces, which raises fears of a massive military operation if the ceasefire fails," Observatory chief Rami Abdel Rahman said.
Elsewhere at least two people were wounded Sunday when a bomb strapped to a motorbike exploded in Hasakeh, the Observatory said.
The blast in a Kurdish-controlled district is one of a series to have hit the northeastern city, most of them claimed by the Islamic State group.
More than 300,000 people have been killed in Syria since the conflict began in March 2011 with anti-government protests.
On Saturday, the White House condemned regime\’s "defiance" of international law after UN experts said the army was responsible for a chemical weapons attack in March 2015.
It was the third chemical weapons attack the UN panel has attributed to government forces.
"We condemn in the strongest possible terms the Assad regime\’s defiance of the longstanding global norm against chemical weapons use," said National Security Council spokesman Ned Price.