After intense fighting, Syrian rebels says siege of Aleppo breached

Rebels say they have breached the siege imposed by the Syrian government on opposition neighbourhoods in the northern city of Aleppo, in a major military breakthrough after intense fighting.

The Syrian government seized the only route into rebel-held areas in northern Aleppo last month, prompting a rebel counteroffensive from the city's south.

The UN said 300,000 people were trapped, making Aleppo one of the largest besieged areas in Syria.

A broad coalition of rebel groups posted videos Sunday of fighters roaming the Ramouseh district, where the siege was breached following overnight clashes. The district houses a number of military colleges.

The war media arm of Lebanon's Hezbollah, the group fighting alongside the Syrian government, conceded the rebels' advance, adding that airstrikes levelled one of the military colleges after forces withdrew.

Rebel fighters to the east of the city, once Syria's commercial capital, have been trying to break through a thin strip of government-controlled territory which separates them from their comrades in the west.

Opposition officials say rebel groups have successfully opened a new route into the city from the southwest.  

The Syrian army, though, denies it has been pushed back and claims it repelled the attack and inflicted heavy causalities in the process. It also says fighting continues.

That means even if the rebel coalition has breached the siege, it's unlikely there are any safe corridors for civilians to get out.

UN urges access to all parts of Aleppo

Humanitarian groups haven't been able to get vital aid into Aleppo for a month.

Farah Dakhlallah, a UNICEF spokeswoman based in Jordan, said an estimated 300,000 people are stuck in eastern Aleppo.

"They've been facing horrendous conditions. Hospitals, clinics, schools and other vital infrastructure have been bombed, sometimes repeatedly. This has had devastating effects for children and their families," she told CBC News.

Dakhlallah said fuel and electricity are scarce, and supplies of clean water are threatened. 

UNICEF is also worried about malnutrition and a high risk of illness among children.

It's calling for immediate and unconditional access to all parts of Aleppo so that aid organizations can bring in water and health supplies.

"We urge the warring parties in Syria to abide by their legal obligations to protect children and all civilians," Dakhlallah said.

She said they do have supplies inside Aleppo delivered before access was cut off, but it's critical they get back in to replenish.