The Bashar al Assad regime hit civilian areas of Aleppo with nearly 30 air strikes on Saturday as the ninth day of deadly bombardments continued, killing nearly 250 people in the city since April 22.
The Syrian regime announced a controversial regime of calm or lull in fighting, to its deadly air strikes late on Friday, but excluded Aleppo from the plan.
In doubt of the regimes sincerity, a number of rebel groups rejected the plan and criticised the United States for not doing enough to stop regime bombardments on civilians.
Upon ongoing criticism, the US on Saturday demanded that Assad's forces halt their bombardment of the city of Aleppo and help restore a nationwide ceasefire.
Fierce bombing has continued in the city, with heavy civilian casualties, while Russia has made it clear it has no intention of restricting its ally Assad's forces.
"We urged Russia to take steps to stop regime violations, especially its indiscriminate aerial attacks in Aleppo," US spokesman John Kirby said.
"The Assad regime continues to escalate the conflict by predominantly targeting innocent civilians and parties to the cessation of hostilities -- not Nusra, as the regime falsely claims."
"Such attacks are direct violations of the cessation and must stop immediately," he declared.
The lull in fighting around the capital and parts of northwest coastal province Latakia, announced by the regime, did not hold through, meanwhile the bombing continued in Aleppo which was excluded from the plan.
The secretary underscored that the initial efforts to reaffirm the cessation of hostilities in Latakia and Eastern Ghouta are not limited to these two areas and that efforts to renew the cessation must and do include Aleppo.
International Law Expert Diala Chehadeh said the regime excluded Aleppo from the ceasefire since it is “crucial for their continuity” to “spend more time in power and to guarantee that they [Assad regime] will stay in power as long as possible.”
Bashar al Assad and his father Hafiz al Assad have been ruling Syria for more than 45 years.
Graphic photos emerged online showing photos of dead children amongst destroyed buildings with torn limbs, indicating the regime and its most loyal ally, Russia, as being responsible for majority of civilian deaths since the start of the six year war.
— Hadeel Emad (@hadeel_maqet) April 30, 2016
Anas Al Abde, president of the Syrian National Coalition, declared that the regime had been violating the February truce on a "daily” basis.
The opposition was ready to reinstate the wider truce, but reserved the right after civilian casualties continued through air strikes by the regime and its ally Russia.
Although the regime and Russia are the only forces with airpower, they have accused opposition groups of ceasefire violations.
The Assad regime did not explain what military or non-military action the "regime of calm" would entail. It said it would last for 24 hours in the capital Damascus and its suburb Eastern Ghouta and for 72 hours in rural areas around the northern city of Latakia.
At least five people were killed in Aleppo early on Saturday in air strikes carried out by Syrian regime warplanes, the Syrian Observatory for Human Rights said.
Aleppo, Syria's largest city before the war, has been divided for years between rebel and regime-held zones. Full control would be a huge prize for Assad, who is regarded as being responsible for fuelling the six year conflict in which more than 400,000 people have been killed and millions displaced.
Of the 250 casualties since April 22, most were killed in bombardments by regime forces. Forty children were reportedly among the dead.
Syrian helicopters later in the day dropped barrel bombs southwest of Damascus, the Syrian Observatory for Human Rights said.
Several explosions were reported.
The United Nations has called on Moscow and Washington to help restore the ceasefire to prevent the complete collapse of talks aimed at ending the war.
Agencies have continued to deliver aid in the west of the country, but say that access is not regular enough and that many Syrians in need still cannot be reached.
Aid access to Madaya and other Syrian towns had been restricted by regime forces and their allies, with at least one million people in besiegement, most facing malnutrition.
At least 20,000 children in the besieged Syrian town of Madaya alone, are at risk of further hunger and starvation, the United Nations Children's Fund said.
The International Committee for the Red Cross said aid had begun to enter the towns of Zabadani and Madaya, where there were reports of starvation earlier this year due to the besiegement.