America has dismissed an eight-hour pause in attacks by Russian and Syrian forces on rebel-held eastern districts of Aleppo as "too little, too late".
Hostilities will be halted for eight hours in the eastern districts of Aleppo, Russia's military announced on Monday, a day on which opposition activists said air strikes killed at least 36 people, including several children, in and around the divided city.
US State Department spokesman Mark Toner said the people of Aleppo "have been subjected to near constant bombardment and air strikes" that have killed many civilians and levelled much of the city's infrastructure in an effort "to starve out and to drive out the opposition and civilians".
"If there is actually an eight-hour pause in the unremitting suffering of the people of Aleppo, that would be a good thing. But frankly, it's a bit too little, too late," he said.
The two militaries will observe a "humanitarian pause" between 8am and 4pm on October 20 to allow civilians and militants safe passage out of the city, Lt Gen Sergei Rudskoi of Russia's general staff said in Moscow.
Militants, the wounded and sick will be allowed to evacuate to the neighbouring rebel-held province of Idlib.
Umited Nations officials have pleaded with combatants to observe weekly 48-hour ceasefires to allow humanitarian relief into the city's besieged eastern districts, but Russian and Syrian forces have only escalated their aerial and ground assault on the rebel-held areas in recent weeks.
The air strikes have claimed hundreds of lives, wounded many, flattened apartment buildings and laid waste to the already crippled medical sector.
But Russian and Syrian leaders are now capitalising on a proposal made by the UN's envoy earlier this month to allow al Qaida-linked militants to leave in exchange for peace and local administration for the eastern districts.
Rebels in the east, along with many residents, spurned the proposition, citing their distrust of the government side. And Russia vetoed a UN Security Council resolution mandating an immediate ceasefire.
Monday's Russian announcement did not include any promises of an extended ceasefire or local administration and followed a bloody day of air strikes on rebel-held districts in and around Aleppo.
At least 23 people were killed in air strike that also wounded dozens in the village of Oweijel, just west of Aleppo, according to the British-based Syrian Observatory for Human Rights. Another monitoring group, the Local Co-ordination Committees, said the air raid was carried out by Russian warplanes and put the death toll at 30.
More than a dozen people were also killed in the Marjeh neighborhood in eastern Aleppo. The Aleppo Media Centre, an activist collective, said those killed included 11 people with the same family name of Qabs ranging from a month-old baby girl to a 25-year-old man.
The Observatory said at least 50 civilians, including 18 children, were killed in air strikes on the eastern part of the city in the 24 hours before the Russian announcement.
Monday's air strikes coincided with the launch in neighbouring Iraq of a major operation by Iraqi and Kurdish forces, backed by the US-led coalition, to retake the northern city of Mosul from the Islamic State group.
There have been concerns the government in Damascus could use the timing of the Mosul offensive to press its onslaught in Aleppo while world attention is diverted to developments in Iraq.
Meanwhile, Syrian state media claimed 49 rebels were killed and wounded in fighting in the neighbourhoods of Sheikh Saeed and Shurfa on the southern edges of Aleppo.
In the nearby province of Idlib, a US-led coalition drone struck a car in the provincial capital that carries the same name, killing all inside, according to the observatory and a jihadi official.
It was not immediately clear who was in the vehicle, but such attacks have previously targeted officials with al Qaida's affiliate in Syria, known as Fatah al-Sham Front.
The observatory said the attack targeted a faction commander and an official with Fatah al-Sham Front, formerly known as Nusra Front, said all those in the car were "martyred".
Earlier this month, a drone attack killed top al Qaida leader Ahmed Salama Mabrouk.