Syrian President Bashar al-Assad, right, speaks with U.N. envoy Staffan de Mistura in Damascus, Syria, in November. (Syrian Arab News Agency via AP)

Concerns about President Bashar al-Assad’s growing vulnerability and gains by the extremist Islamic State group are generating a burst of diplomacy among world powers to end Syria’s civil war, analysts say.

Officials from Russia, the United States and several Middle Eastern countries — including Iran, a key ally of Assad — have held a flurry of recent meetings and discussions about the four-year-old conflict.

Few expect immediate breakthroughs, but the diplomatic activity has raised hope in some circles of possible movement toward an eventual resolution to a war that has empowered extremist groups, killed an estimated 250,000 people and displaced millions.

“What’s helping to drive all this diplomacy is the fact that all of these countries are united in concern over the Islamic State, which is a threat not just to Syrians but the international community,” said Mohammed Obeid, a Lebanese political analyst who is close to the Syrian government.

He speculated that the diplomacy also may have been spurred by “new goodwill” from a landmark nuclear agreement reached last month between world powers, led by the United States, and Iran.

Last week, Iranian Foreign Minister Mohammad Javad Zarif met with Assad in the Syrian capital, Damascus, to discuss an Iranian plan to end the civil war.

His visit coincided with an unusual cease-fire that Iranian officials, acting on behalf of the Assad government, brokered with rebel groups in three Syrian towns. The truce was hammered out in Turkey, an ardent opponent of Assad.

Perhaps the most active player in all the diplomatic activity is Russia, an Assad ally. Moscow has initiated discussions with Syrian opposition leaders and Saudi Arabia, which backs Syrian rebel groups, including al-Qaeda-affiliated Jabhat al-Nusra. Russian Foreign Minister Sergei Lavrov held discussions over Syria in Qatar this month with U.S. Secretary of State John F. Kerry and Saudi Foreign Minister Adel al-Jubeir.

Despite all the diplomacy, however, long-standing sticking points remain, including perhaps the most difficult one: what to do with Assad. The United States has long said that any peace deal must require the Syrian leader’s eventual departure. Iran and Russia reject this position.

That issue helped scuttle previous peace talks. And the dispute over Assad’s fate does not appear to have eased, even as rebels groups and Islamic State militants have seized significant territory from the Syrian government in recent months. Some of the captured territory is close to government strongholds along Syria’s northwestern coastline, adding to speculation that Assad’s grip on power is slipping. The Syrian leader now controls less than half of Syria.

Julien Barnes-Dacey, a Syria expert at the European Council on Foreign Relations, ascribed the new diplomacy in part to mounting fears about Assad’s durability. But officials from opposing sides of the conflict appear to be primarily using the meetings and discussions to test each other’s boundaries.

“I don’t think there’s a collective readiness for compromise yet,” Barnes-Dacey said.

In other arenas, the diplomatic surge may be producing some dividends. On Monday, the U.N. Security Council unanimously approved a statement backing preliminary talks aimed at restoring peace to Syria. Although nonbinding and largely symbolic, the measure marks rare agreement between Russia and the United States, both veto-wielding countries in the 15-member body, over the Syrian war.

The agreement gives backing to a new peace effort announced by Staffan de Mistura, the United Nations’ special envoy to Syria.

He plans to hold simultaneous talks with Syrian parties on key aspects of the 2012 Geneva road map, an internationally supported framework for ending the conflict. The road map calls for transferring authority to a transitional government, although it does not say whether Assad would play a role in it.

Emile Hokayem, a Middle East analyst at the London-based International Institute for Strategic Studies, expressed doubt that the U.N. envoy’s new plan would work. Differences over how to resolve the conflict are probably still too great, while groups that are still fighting do not appear to be ready for a diplomatic solution.

“When you look at Syria, you realize that it’s the local dynamics — not these regional powers — that are the main driver of the conflict,” Hokayem said.

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