BEIRUT/GENEVA A deal in Syria being discussed by the United States and Russia, which would involve a country-wide ceasefire and focus on delivering aid to embattled Aleppo, could be announced soon, Washington's Syria envoy has said.
The deal would oblige Russia to prevent Syrian government warplanes from bombing areas held by the mainstream opposition, and would require the withdrawal of Damascus's forces from a key supply route north of Aleppo, according to a letter from Michael Ratney to the armed opposition, seen by Reuters and dated Sept. 3.
In return, the United States would coordinate with Russia in fighting against al Qaeda, the letter said, without elaborating.
It said the rebels must cooperate in order for the agreement to take effect, but that guarantees were being sought that Moscow, Syria's most powerful ally, would respect the deal.
A truce brokered by the Cold War foes in February collapsed and peace talks crumbled earlier this year, with the Syrian government side and the opposition accusing each other of violating it.
Fighting has since escalated across the country, particularly around divided Aleppo, where advances by both sides have cut supplies, power and water to nearly 2 million people in government- and rebel-held areas.
The latest agreement would see government forces withdraw from a key supply route which led into the rebel-held east of the city and which was cut in July. The Castello Road would become a demilitarised zone, Ratney's letter said.
The government and rebels would also be required not to block any aid entering the city, it said.
(Reporting by John Davison and Tom Miles; Editing by Mark Potter)