The presidents of Turkey, Iran and Russia on Friday failed to agree on a ceasefire that would forestall a Syrian goverment offensive in rebel-held Idlib province which the United Nations fears could cause a humanitarian catastrophe involving tens of thousands of civilians.
Turkey's Tayyip Erdogan, Russia's Vladimir Putin and Iran's Hassan Rouhani, meeting in Tehran for a summit of key foreign players in Syria's war, agreed in a final statement that there could be no military solution to the conflict and it could only end through a negotiated political process.
But as Syrian government and Russian warplanes mounted air strikes in Idlib yesterday morning in a possible prelude to a full-scale offensive, Putin and Rouhani pushed back against Erdogan's call for a truce.
The Turkish leader said he feared a massacre and Turkey could not accommodate any more refugees flooding over its border.
Putin said a ceasefire would be pointless as it would not involve Islamist militant groups it deems terrorists. Rouhani said Syria must regain control over all its territory.
Idlib is the insurgents' only remaining major stronghold and a government offensive could be the war's last decisive battle.
Tehran and Moscow have helped Assad turn the course of the war against an array of opponents ranging from Western-backed rebels to the Islamist militants, while Turkey is a leading opposition supporter and has troops in the country.
Their discussions in Tehran mark a crucial point in a seven-year-old war which has killed more than half a million people and forced 11 million to flee their homes.
In the final statement, the three agreed on the need to eliminate Islamic State, the Nusra Front, and other groups linked to al-Qaeda and designated as terrorists. But there were other armed opposition groups who could join any ceasefire agreement, they said.
The communique also called on the United Nations and the international community to step up humanitarian aid to Syria and help in restoring basic infrastructure assets. Efforts must be made to protect and to create conditions for the safe return of refugees, it added.
Meanwhile, the fate of Idlib hung in the balance.
The United Nations Security Council met to discuss Idlib yesterday at the request of the United States, and UN Syria mediator Staffan de Mistura said there were "all the ingredients for a perfect storm".
"The dangers are profound that any battle for Idlib could be, would be a horrific and bloody battle," de Mistura said.