LONDON -- The United States and 10 Arab and European nations expressed support Tuesday for convening a peace conference next month in Geneva to begin negotiations on a political settlement to end the bloody Syrian civil war. But U.S. Secretary of State John Kerry acknowledged that Syria's moderate opposition had not yet decided whether it would attend.
"They have to make up their mind," Mr. Kerry said at a London news conference. "And none of us are going to prejudge what they will do in that process."
Ahmad al-Jarba, president of the Syrian opposition coalition, and other rebel opposition leaders are to assemble next week and discuss whether to participate, Mr. Kerry said.
The communique issued by the London 11, as the nations were known, addressed several themes important to the Syrian opposition. It reiterated that a transitional government should be established as part of a political settlement, and said that when it was formed, President Bashar Assad and his close associates "with blood on their hands will have no role in Syria."
That element of the communique alone could pose an enormous obstacle to a peace conference. Mr. Assad asserted Monday that he would not only serve out his term, but is also thinking about running for re-election in 2014.
The communique also called for stepping up support to the political and military wings of the moderate Syrian opposition and for improving its ability to meet the needs of the Syrian population in the areas it controls.
But the communique was notably lacking in some important specifics. It warned against "delaying tactics" and expressed hope that a transitional government would be established "within the coming months." At the same time the communique set no firm deadline for creating the transitional government, which is to be established by "mutual consent" of opposition members and Syrian government representatives. Nor did it give details of what additional assistance is to be provided to the rebels.
The document outlined a series of "confidence-building measures," such as calling on the government to end its "siege of urban areas" and establishing local cease-fires to allow delivery of humanitarian aid to hungry and beleaguered civilians. But those measures will be listed as objectives for the Geneva "process," not as prerequisites to the meeting next month.
The moderate opposition has been wary of being drawn into open-ended talks while the Assad government presses its attacks, fearing that such a move would undermine its credibility with Syrians inside the country after more than two years of war.
In a BBC radio interview before the London meeting, British Foreign Secretary William Hague argued that it was important to strengthen the moderate opposition to counter inroads made by Islamic extremists. "The reason we have to make sure we are supporting and dealing with the moderate opposition committed to a democratic, pluralistic, nonsectarian future for Syria is precisely because if they don't have a role, then all the Syrian people have got left is a choice between Assad and extremists," he said. "Syrians on all sides now need to make the effort and make the compromises necessary for a peace process to work."
Mr. Kerry said Tuesday that he thought the moderate opposition leaders would ultimately decide to participate in the meeting. "I believe that the conference can happen next month," he said. "I am confident that in the end, the opposition will decide that it is in their best interest."
Mr. Kerry also acknowledged that there have been differences between the United States and Saudi Arabia on Syria. Saudi Arabia has wanted the United States to do more to train and arm rebel fighters. And the Saudi leadership was hoping that President Barack Obama would order a cruise missile attack on the Syrian military in response to what Western and Arab powers said was the Syrian government's Aug. 21 chemical weapons attack near Damascus.
"We know that the Saudis were obviously disappointed that the strike did not take place," Mr. Kerry said, referring to the cruise missile attack the White House had planned before it seized on a Russian alternative proposal to eliminate Syria's chemical weapons program.
Saudi Arabia has also been worried that the Obama administration may be too eager to seek a compromise with Iran over its nuclear program and was unhappy that Washington did not take a stronger stance against the Muslim Brotherhood when President Mohammed Morsi governed Egypt.
Mr. Kerry said he had discussed these issues with Prince Saud Al-Faisal, the Saudi foreign minister, when he met with him Monday in Paris.
Saudi Arabia was among the 11 nations that issued the communique Tuesday, and Mr. Kerry insisted that the Saudis and Americans were now "on the same page" regarding Syria.