From left, Turkish Minister Sinirlioglu, Secretary of State Kerry, Saudi Minister al-Jubeir and Russian Minister Lavrov in Vienna on Friday. Photo: carlo allegri/Reuters
Jay Solomon and
Valentina Pop
Updated Oct. 23, 2015 5:39 p.m. ET

VIENNA—The U.S., Russia and a group of European and Middle Eastern countries are preparing international talks as early as next Friday to accelerate efforts to end the war in Syria, Secretary of State John Kerry said.

It wasn’t decided if Iran would take part in the meeting, he said. But European countries are pressing for Tehran’s inclusion.

Mr. Kerry is visiting Jordan and Saudi Arabia this weekend for further consultations.

Iran and Russia are the primary backers of Syrian President Bashar al-Assad. Tehran and Moscow launched joint military operations in Syria last month to strengthen the regime’s position.

Mr. Kerry said any effort to end more than four years of fighting in Syria must have the backing of the Mideast’s major powers.

“The hard work of shaping that transition [in Syria] requires an international approach and a consistent approach,” Mr. Kerry said following a meeting in the Austrian capital with Saudi Arabia, Turkey and Russia. “There remain differences among us about exactly what the final approach looks like.”

European Union foreign policy chief Federica Mogherini spoke in favor of including Iran. “All relevant actors, regionally and internationally should be involved,” she said. “I hope that Iran can be part of this common effort.”

Drone footage from Oct. 18 shot by a Russian production company shows the destruction and fighting around the Syrian capital of Damascus.

The key issue dividing the major powers remains the future of Mr. Assad. The U.S. and its European and Arab allies insist that a peaceful solution is impossible while Mr. Assad remains in power. The Arab dictator has used chemicals and barrel bombs against his people, according to outside observers, leaving hundreds of thousands dead.

Saudi Arabia’s Foreign Minister Adel al-Jubeir said following the meeting that divisions remain about the future of Mr. Assad, who met with Russian President Vladimir Putin in Moscow on Tuesday.

“There still remain some gaps with regards to the departure of Bashar al-Assad and the timing of such a departure,” Mr. al-Jubeir said. “We will continue such conversations perhaps with a broader range of countries in order to see if we arrive at a consensus on the way forward for Syria.”

Russia made progress on forging a more united position on Syria with one Arab country: Jordan. Moscow and Amman announced they were establishing an office in Jordan’s capital to better manage their military operations in Syria. Jordan is a leading member of a U.S.-led coalition to attack Islamic State in Syria and Iraq.

Mr. Putin has doubled up his support for the Syrian dictator over the past month by launching airstrikes against rebel groups seeking his overthrow. The Kremlin has closely coordinated its military operations with the Syrian regime as well as Iran and the Lebanese militia Hezbollah.

These combined forces have reclaimed territories previously lost to the insurgents.

Mr. Kerry and other U.S. officials have expressed hopes the Russians will agree to a political transition that will eventually see Mr. Assad exit Syria’s political scene, even if he is allowed to remain in office for a time.

“The fate of the Syrian president must be decided by the Syrian people,” Russian Foreign Minister Sergei Lavrov said in Vienna after announcing the Jordan agreement.

Saudi Arabia and Turkey are major backers of insurgent groups that have been fighting against the Syrian regime.

Mr. Putin said on Thursday that he had received permission from Mr. Assad to offer support to rebels in Syria who are prepared to “really fight” against Islamic State extremists. It wasn’t immediately clear which opposition groups would fit the Kremlin’s criteria. Mr. Assad himself and members of his regime have called on rebels to join regime forces in fighting Islamic State on many occasions over the past couple of years.
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