Aleppo was left out of a new temporary US-Russian brokered truce that appeared to be holding in the regime stronghold of Latakia as well as Damascus and the nearby rebel bastion of Eastern Ghouta.

US Secretary of State John Kerry was to travel Sunday to Geneva in a show of support for the truce and will meet the UN envoy to Syria and the Jordanian and Saudi foreign ministers.

The State Department said his talks will focus on "efforts to reaffirm the cessation of hostilities nationwide in Syria".

A new round of UN-backed peace talks is set to start on May 10 in Geneva.

In Aleppo's rebel-held east dozens of civilians left the battered Bustan al-Qasr district early Saturday an AFP correspondent said.

"The situation has become unbearable" Abu Mohammed said as he prepared to flee with his wife and five children. "Everything is paralysed."

Russia said that it would not ask Damascus to halt air raids on Aleppo.

"No we are not going to put pressure on (Damascus) because one must understand that the situation in Aleppo is part of this fight against the terrorist threat" Deputy Foreign Minister Gennady Gatilov said.

Washington has appealed to Moscow to keep President Bashar al-Assad's regime in check.

Once Syria's economic hub Aleppo and its surrounding countryside have suffered some of the worst fighting in a conflict that has killed more than 270000 people and displaced millions.

- Watching the sky -

At least 246 civilians have died in shelling rocket fire and air strikes in both sides of the city since April 22 the Syrian Observatory for Human Rights monitor said.

At least 10 civilians died in rebel-controlled areas on Saturday the civil defence said.

The few people out on the streets watched the sky anxiously for regime aircraft running for shelter when one launched a new raid.

The Britain-based Observatory which relies on a network of sources on the ground reported 28 air strikes on eastern neighbourhoods.

But in its daily report on Syria Russia's defence ministry said it had recorded only "three ceasefire violations in the city of Aleppo" blaming them all on the rebels.

The SANA state news agency said shelling of western government-held neighbourhoods killed three civilians including a child and blamed Al-Qaeda affiliate Al-Nusra Front and its allies.

A pro-government newspaper said Thursday the army was preparing an offensive to recapture all of Aleppo and the surrounding province.

Some families have fled to safer districts while others left by the dangerous Castello road the only route out of near-besieged east Aleppo.

Hospitals have also been bombed in nine days of escalating violence in Aleppo.

Four medical facilities were hit Friday on both sides of the front line the International Committee of the Red Cross said.

A raid on Wednesday hit a hospital supported by Doctors Without Borders and the Red Cross as well as nearby housing killing 30 people and sparking an international outcry.

On other fronts fighting halted at 1:00 am Saturday (2200 GMT Friday) in a "freeze" set to last for 24 hours in Damascus and Eastern Ghouta and 72 hours in Latakia.

- Aid for besieged towns -

Humanitarian convoys carrying food and medicine meanwhile entered the besieged rebel-held towns of Madaya and Zabadani northwest of Damascus on Saturday the Red Cross said.

At the same time trucks entered the besieged government-held towns of Fuaa and Kafraya southwest of Aleppo.

Madaya became infamous in late 2015 after dozens died of starvation there.

In the eastern province of Deir Ezzor a couple and their two daughters were killed in strikes by unidentified aircraft on a village held by the Islamic State group the Observatory said.

And in northeastern Syria a suicide bomber killed five Kurdish policemen at a checkpoint in the city of Qamishli police said.

The violence in Aleppo has severely tested the February 27 truce between the regime and non-jihadist rebels intended to pave the way to an end to the five-year conflict.

Anas al-Abdeh head of the Istanbul-based opposition National Coalition Saturday accused the regime of "war crimes and crimes against humanity" in Aleppo.

Human Rights Watch also said the air strikes on medical facilities in the city "may amount to war crimes".

Qatar called for an emergency Arab League meeting and Saudi Arabia condemned the regime strikes.