ISTANBUL — Turkey and the United States agreed Saturday to accelerate preparations for the possible fall of Syria’s president, Bashar Assad, creating a formal bilateral team to manage helping the opposition, providing aid to fleeing refugees, and planning for worst-case outcomes that include a chemical weapons attack.
At a news conference here, Secretary of State Hillary Rodham Clinton and Turkey’s foreign minister, Ahmet Davutoglu, said that with the situation in Syria growing more dire, as the battle for Aleppo continues to rage, it was time to create a nerve center for information sharing and planning. They said a unified task force with intelligence, military, and political leaders from both countries would be formed immediately to track Syria’s present and plan for its future.
‘‘What the minister and I agreed to was to have very intensive operational planning,’’ Clinton said. ‘‘We have been closely coordinating over the course of this conflict, but now we need to get into the real details.’’
Clinton, who also announced an additional $5.5 million in humanitarian aid for refugees, left open the possibility of setting up a no-fly zone, suggesting that the new planning team assigned to perform an intense analysis of all options could be a precursor to more direct assistance. But she stopped short of describing specific plans for helping Syria’s opposition fighters now.
The day after protesters in Aleppo chanted ‘‘Arm us with antiaircraft weapons,’’ US officials said the United States remained concerned about providing weapons or air support because it could draw a violent response, not just from Syria, but also from Russia, Iran, and other allies of Assad’s that have strongly opposed direct foreign intervention to topple the government.
Hinting at fears of a wider war, Clinton said Saturday that the goal was to hasten the removal of Assad but ‘‘not in a way that produces even more death, injury, and destruction.’’
Turkey is a natural hub for any kind of action in Syria. A former Syrian ally, it declared its allegiance with the rebels; many Syrian opposition groups are based in Turkey; and its border with Syria has become the main distribution point for weapons and assistance to the rebels, who have opened an on-again-off-again supply corridor from the border to Aleppo.
On Saturday, Davutoglu spoke more forcefully than Clinton on the need for action. Describing the humanitarian crisis in Aleppo and the plight of refugees fleeing on roads under attack from Syrian forces, he said, ‘‘The international community needs to take some very decisive steps to stop this.’’
But in practice, analysts said the United States and Turkey, along with a wider group of allies known as the Friends of Syria, continue to hold back. Saturday’s announcement still amounts to a policy of life support, some argue, giving enough help to keep the rebel movement alive and minimizing intervention while figuring out what to do next.
‘‘The friends of Syria have developed a stake in making sure the opposition is simply not wiped out,’’ said Ilter Turan, an international relations professor at Bilgi University in Istanbul. ‘‘That becomes the ruler to measure this by.’’
After 17 months of conflict and at least five months of the US focus on ‘‘nonlethal assistance,’’ some signs of international help have, in fact, recently been seen. More rebel commanders in Syria have satellite phones and ways to mask their communications. Qatar and Saudi Arabia have been leading the effort to arm Assad’s opponents, and US intelligence officials have helped select recipients, according to US officials.
Rebels and activists say such assistance so far has been nowhere near enough.
‘‘We don’t want food or money; all we need are weapons. We are running low,’’ said Abu Mohammed, a rebel brigade commander in Aleppo, where fighting continued to rage on Saturday. ‘‘We need antiaircraft missiles and we have a big need for live ammunition.’’
The meeting between Turkey and the United States was part of a flurry of diplomatic activity that underlines the severity of the crisis and the fears of escalating war.
Arab foreign ministers plan to meet on Sunday in Jiddah, Saudi Arabia, to discuss developments in Syria and to consider selecting a replacement for Kofi Annan, the United Nations-Arab League envoy.