The UN special envoy to Syria has called for a truce again around the city of Aleppo as activists report more deaths in fighting around the country.
Activists said 33 people were killed in fighting in Aleppo on Saturday when air strikes targeted the city's southern edges and intense battles raged, the AFP news agency reported.
Meanwhile, in northeastern Syria 25 people have been killed in air strikes in Hasaka, according to the Britain-based Syrian Observatory for Human Rights (SOHR).
Activists said government forces attacked the mainly Kurdish city for a third day on Saturday.
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Staffan de Mistura, the UN envoy, has long called for a 48-hour halt in fighting each week to allow aid delivery and medical evacuations from both rebel-held eastern and government-controlled western Aleppo.
"You may wonder what's the good of a truce in such a terrible war. Well, I can assure you and I've seen it in the past that a truce can save lots of lives and is a breath of fresh air for people being besieged," De Mistura said on Saturday.
"A truce can give the possibility for people to stop and think that it is probably best to negotiate because no one is winning and those who are losing their lives are the Syrians."
|Images of fve-year-old Aleppo bombing survivor Omran Daqneesh have shocked the world [Al Jazeera]
Among those who died in Aleppo on Saturday was the older brother of Omran Daqneesh, the little Syrian boy who was pictured sitting in an ambulance dazed and covered in blood after an air strike.
Ali Daqneesh died from wounds sustained in the August 17 attack on the family's apartment in Aleppo, according to the SOHR.
"Ali, aged 10, succumbed to his injuries. He was badly wounded in the same bombardment as Omran ..."
Igor Konashenkov, Russia's defence ministry spokesman, announced on Friday that his country was "ready to implement the first 48-hour 'humanitarian pause' to deliver humanitarian aid to Aleppo residents" next week.
De Mistura welcomed the move and said the UN was counting on Russia's help to ensure "the adherence of the Syrian armed forces to the pause, once it comes into effect".
More than 300 civilians have been killed in a three-week surge of fighting and bombardment in Aleppo city, a monitoring group said on Saturday.
The battle for Syria's second city has killed 333 civilians since July 31, when rebels launched a major push to break a government siege of districts under their control.
The toll includes 165 civilians - among them 49 children - killed in opposition fire on the city's government-held western districts.
Another 168 civilians died in Russian and Syrian government air strikes and shelling on its rebel-controlled eastern neighbourhoods, according to the SOHR.
Russia has been carrying out air raids in support of President Bashar al-Assad's forces in Syria since September 2015.
Another 109 people were killed in bombardment across the rest of Aleppo province during the same period, the SOHR said.
More than 290,000 people have been killed since Syria's conflict started in March 2011 and international efforts at putting an end to the war have faltered.
Source: Al Jazeera and agencies