Syria conflict

Activists say a village school was targeted in rebel-held Idlib.

The UN also warned that the coming winter could be the worst yet in Syria's five-year-long civil war.

Its Syria humanitarian effort head, Jan Egeland, said the brutal conflict had become more ruthless.

He said it was affecting increasing numbers of civilians.

Unicef said that, including the one in Idlib, five Syrian schools had been targeted since 11 October in "simply inhuman" attacks.

Residents said warplanes began bombing the city in the latter half of Sunday.

"The bombing started again," a Syrian White Helmet rescue worker named Ismail Abdullah told CNN by phone from eastern Aleppo.

"I heard a lot of bombing in the night. They were airstrikes."

Civilians urged to evacuate

The Syrian government and its close ally Russia announced the start of the ceasefire last Tuesday.

Originally, it was only expected to last eight hours, but ended up stretching several days.

Russia has helped bolster the Syrian regime's airstrikes on rebel-held parts of Aleppo, Syria's largest city and thesite of a humanitarian catastrophe.

Gen. Sergey Rudskoy announced airstrikes will stop for eight hours Thursday, starting at 8 a.m.

He also urged rebels to leave the city via two corridors to Idlib.

US Secretary of State John Kerry described the situation as "the largest of humanitarian disasters".

He said that Russia needed to understand that "this war cannot end without a political solution".

Mr Kerry is in London taking part in talks aimed at finding a peaceful solution to the Syria conflict.

Speaking alongside the UK's Foreign Secretary Boris Johnson, he said that "crimes against humanity" were taking place daily in Aleppo.

Mr Johnson also urged Russia to "do the right thing by humanity and the people of Syria" by committing to a ceasefire.

On Saturday he met Russia's Foreign Minister, Sergei Lavrov, along with representatives from other countries with stakes in the five-year conflict.

Nothing concrete came from that but both the US and Russia spoke of "ideas" emerging.

A ceasefire brokered last month collapsed after just a few days.

Since then Syrian forces, backed by Russia, have been bombing the city of Aleppo - the most high-profile battleground in the country's civil war - in what Washington has called a war crime.

"I believe it is the international community's first priority to be able to end this conflict," he told the BBC.

Mr Guterres said the world now faced a dangerous moment, with even countries far from warzones threatened by acts of terrorism.

He called the drive to end armed conflict "a battle for values".

In his first interview since his unanimous election, Mr Guterres told the BBC's Lyse Doucet world leaders had a "vital shared interest" in ending Syria's war, and the global strife that is linked to it.

Washington broke off all negotiations with Moscow nine days ago amid extreme tension over failure to secure a truce.

But Russia's Foreign Minister Sergei Lavrov will now meet his US counterpart John Kerry and other key regional powers in Switzerland on Saturday.

The announcement comes after two days of renewed air strikes on Aleppo, killing at least 75 people.

The US State Department said Mr Kerry would discuss a "multilateral approach" to ending the crisis, "including a sustained cessation of violence and the resumption of humanitarian aid deliveries."

At least 25 people are reported to have died, including children.

The bombardment follows a temporary lull called by the Syrian government, partly to allow civilians to leave rebel areas in the east of the city.

It has come under intense aerial attack since a ceasefire brokered by the US and Russia collapsed last month.

The air strikes came as Russian President Vladimir Putin cancelled a planned visit to France.

He had been due to meet French President Francois Hollande and open a new Orthodox church later this month.

But after France's government said talks would be confined to Syria the visit was halted, French presidential sources said.

On Monday, Mr Hollande suggested Russia could face war crimes charges over its bombardment of Syria's city of Aleppo.

The French presidency had told the Russians Mr Hollande would attend only one event with Mr Putin during the visit planned for 19 October - a working meeting on Syria, according to the sources.

"Russia, and the regime, owe the world more than an explanation about why they keep hitting hospitals and medical facilities and children," he said.

"These are acts that beg for an appropriate investigation of war crimes."

Moscow has repeatedly denied attacking civilians, and said it targets terrorist groups in Syria.

Mr Kerry, however, said Russian and Syrian government attacks on hospitals were "beyond the accidental" and part of a deliberate strategy in war-torn Syria.