Iran's foreign minister on Tuesday hailed an agreement between Turkey and Russia to avert an assault on Syria's last major rebel stronghold in Idlib province as an example of "responsible diplomacy."
After more than four hours of negotiations in the Black Sea resort of Sochi on Monday, regime ally Russia and rebel backer Turkey agreed to create a demilitarised zone around the opposition bastion.
"Intensive responsible diplomacy over the last few weeks ... is succeeding to avert war in Idlib with a firm commitment to fight extremist terror," Iranian Foreign Minister Mohammad Javad Zarif wrote on Twitter.
"Diplomacy works," he added, pointing to his visits to Ankara and Damascus as well as a three-way summit between the leaders of Iran, Russia and Turkey earlier this month.
Asked at a press conference on Tuesday whether Iran was consulted about the Sochi decision, Zarif said: "Yes, Iran has always been at the centre of consultations."
Tehran and Moscow are key supporters of President Bashar al-Assad in the country's seven-year civil war, while Ankara backs opposition fighters seeking the ouster of the Syrian leader.
Russian President Vladimir Putin and his Turkish counterpart Recep Tayyip Erdogan agreed on Monday to create a 15-20 kilometre-wide buffer zone along the line of contact between rebels and regime troops by October 15.
The agreement entails the "withdrawal of all radical fighters" from Idlib as well as "heavy weaponry from this zone," Putin said.
Russia blames Israel for loss of aircraft to Syrian fire
Russia blamed Israel on Tuesday for the loss of a military jet to Syrian fire, which killed all 15 servicemen on board, and threatened a response.
Israeli pilots carrying out attacks on Syrian targets "used the Russian plane as a cover, exposing it to fire from Syrian air defences," Russian military spokesman Igor Konashenkov said in televised remarks.
An Israeli air force's F-16 launched an attack on targets near Syria's Latakia on Monday around 10pm when a Russian Il-20 was landing, he said.
"The Il-20, which has a much bigger reflective surface than the F-16, was struck down by an S-200 rocket," he said.
"As a result of irresponsible actions of Israeli military, 15 Russian servicemen have died."
"We consider these provocative actions by Israel as hostile," he said, adding that "we reserve our right for a proper response."
Konashenkov said Israel notified Russian command about its plan to bomb targets in Syria's Latakia province only one minute in advance which "did not allow for the Russian plane to be moved to a safe zone."
A search and rescue operation for the remains of the Russian plane was ongoing.