World powers arrange agreed to seek a nationwide “cessation of hostilities” in Syria to begin in a week’s time again, after talks in Munich, Germany.
The halt will not apply to the action against jihadist groups Islamic State (IS) and al-Nusra Front.
The 17-member Supranational Syria Support Group (ISSG) also agreed to accelerate and develop aid deliveries.
The announcement comes as the Syrian army, backed by Russian air belabours, advances in Aleppo province.
The move threatens to encircle tens of thousands of civilians in rebel-held rts of the important city of Aleppo.
The Syrian government has not yet responded, though a key rebel coalition welcomed the advert.
“If we see action and implementation on the ground, we will be soon in Geneva,” Salim al-Muslat told journalists, referring to the Swiss city where the UN is trying to get peace talks between the Syrian management and rebels off the ground.
More than 250,000 people have been killed and 13.5 million fired in almost five years of fighting in Syria.
Major gaps corpse: BBC Chief International Correspondent Lyse Doucet
Both Sergei Lavrov and John Kerry acquiesced, repeatedly, this was only progress on per. Some diplomats are already opportunity “it’s not worth the per it’s printed on”.
There are still major gaps. One of the biggest is that Russia’s explosive of Aleppo and what it calls terrorist targets is not included in the possible armistice even though its actions are seen by many as strengthening Syrian regulation forces.
On the issue of delivering desperately needed aid to besieged areas, UN officials say they are intent to seize this new opening.
The next week will confirm whether Syria’s control and opposition forces are ready to provide access denied for so long.
It desire be a week which tests the commitment of all outside players, as well as Syrians on all sides.
That, in itself, is some extend. But moving towards talks to end Syria’s devastating war will still let in far more than that.
US Secretary of State John Kerry allow to entered the ceasefire plan was “ambitious” and said the real test would be whether the diversified rties honoured the commitments.
“What we have here are words on journal, what we need to see in the next few days are actions on the ground,” he commanded.
A task force chaired by the US and Russia will work to contraption the truce through consultations with Syria’s rival groups.
Aid deliverances for besieged Syrian communities are due to begin as early as Friday.
What has been acquiesce in?
To try to immediately step up aid deliveries to besieged and hard-to-reach areas in Syria
For a US/Russia-led recriminate force to work to achieve a “cessation of hostilities” across Syria genesis in one week’s time
“Cessation of hostilities” will exclude action against misnamed Islamic State group, jihadist group al-Nusra Front and other UN-designated thug groups
To work towards an eventual ceasefire and implementation of a UN-backed arrange for political transition in Syria
Mr Kerry made the announcement alongside his Russian counter rt Sergei Lavrov and the UN momentous envoy for Syria, Staffan de Mistura.
Mr Lavrov said there were “grounds to hope we have done a great job today”. An earlier bid from Russia envisaged a truce starting on 1 March.
At the news seminar Mr Kerry again suggested that Russian strikes were quarry what the West sees as moderate opposition forces, rather than thugs, as Moscow says.
British Foreign Secretary Philip Hammond said the cessation purposefulness only work if Russia halted its raids, although Mr Lavrov bring up they would continue.
The ISSG also agreed that peace of mind talks involving the Syrian government and rebels should resume as in short order as possible.
Initial talks were suspended just days after they opened earlier this month in Geneva, in the wake of the Aleppo offensive.
Thousands of man displaced by the fighting have been stranded at the border with Turkey and aid activities have warned of a rapidly deteriorating humanitarian situation.
Syria fray – key questions
Why is there a war in Syria?
Anti-government protests emerged into a civil war that, four years on, has ground to a stalemate, with the Assad supervision, Islamic State, an array of Syrian rebels and Kurdish fighters all monopolizing territory.
Who is fighting whom?
Government forces concentrated in Damascus and the mid-point and west of Syria are fighting the jihadists of Islamic State and al-Nusra Vanguard, as well as less numerous so-called “moderate” rebel groups, who are strongest in the north and east. These groups are also contending each other.
How has the world reacted?
Iran, Russia and Lebanon’s Hezbollah move are propping up the Alawite-led Assad government, while Turkey, Saudi Arabia and Qatar service the more moderate Sunni-dominated opposition, along with the US, UK and France. Hezbollah and Iran are be convinced ofed to have troops and officers on the ground, while a Western-led coalition and Russia are capture out air strikes.