U.N. special envoy for Syria Staffan de Mistura, second right, attends a meeting with Syrian government representatives at the United Nations in Geneva on Feb. 28, 2017. (AP)

The vacuum in U.S. policy on Syria is being keenly felt at the latest round of peace talks aimed at negotiating a political solution to the Syrian war — talks that seem destined to wind down this week without meaningful progress.

Five days into a round of discussions intended to take place between delegations representing the Syrian government and the opposition, government and opposition negotiators still have not met. Instead, the talks, due to end Friday, have become snarled in debates about procedures and process without yet addressing the major issues surrounding the remote possibility of finding a political solution to the nearly six-year-old war.

These talks, known as Geneva IV because they represent the fourth round of discussions aimed at securing a political settlement on the basis of a communique drafted in Geneva by the United States and Russia in 2012, are taking place against the backdrop of a new regional balance of power in which Russia has the leading role in Syria.

For the first time, the United States is not taking the initiative in pushing for a negotiated settlement. The rout of rebels from their stronghold in eastern Aleppo in December was a defeat for U.S. policy as well as for the Syrian opposition, and it effectively left a vacuum of U.S. decision-making on Syria that has yet to be filled by the new Trump administration.

Although Russia has since sought to position itself as a mediating power between the government and the opposition, there are growing questions over how much pressure it is prepared to put on President Bashar al-Assad to make concessions, diplomats said. Russia’s veto of a U.S.-backed U.N. Security Council resolution Tuesday that would have imposed sanctions on the Assad government for its continued use of chemical weapons has further exposed the gulf between opposition and Russian perspectives on the war.

Syrian Ambassador to the United Nations and head of the government delegation Bashar al-Jaafari, arrives for peace talks at the Palais des Nations in Geneva on Feb. 28, 1017. (Xu Jinquan/Pool Photo via AP)

“We all desperately need the U.S. to engage in this and drive this forward with the Russians. The process is skewed in one direction. There is no other counterweight,” said a Western diplomat attending the talks, who spoke on the condition of anonymity because of the sensitivity of the subject. “There is a vacuum here, and I am not sure the Russians have enough incentive to move forward to fill the vacuum.”

U.S. diplomats have been present at the talks alongside representatives of European and regional allies. But until the Trump administration articulates its policy on Syria, participants and diplomats said, there is little reason for either the Syrian government or the opposition to make substantial concessions.

Both sides have been encouraged by President Trump’s often contradictory statements on the Middle East to think that the new administration may shift its policy in their favor.

His emphasis on the importance of fighting the Islamic State has raised hopes in Damascus of the United States dropping its support for the Syrian opposition and joining an alliance with Assad against terrorism.

As was the case in previous years, Bashar al-Jaafari, the lead negotiator for the Assad government, has stressed that the focus of the talks should be on fighting terrorism, not on a political transition from Assad’s rule that the United States had demanded in previous years or the milder political reforms that Russia has been promoting.

The opposition is likewise optimistic that Trump’s pledges to roll back Iranian influence will translate into more robust support for the rebels than was the case under the Obama administration. Assad owes his survival in large part to Iran’s immense support, and backing Assad means empowering Iran in Syria, opposition figures argue.

Mindful that it has much to lose or gain from whatever the Trump administration decides, the opposition delegation has sought to be on its best behavior. It announced ahead of the talks that it would not walk out — as it did last time — and it has agreed to discuss all the items on the agenda set by Staffan de Mistura, the U.N. envoy mediating the discussions.

“Our aim now is to continue with the political process to show Mr. Trump we are serious about a relationship, about a political solution and about limiting the role of Iran,” said Nasr al-Hariri, head of the opposition delegation. “But if the U.S. vacuum continues, I think Mr. de Mistura will face a lot of obstacles on the way to a political solution.”

A review of U.S. policy on Syria is expected to be included in a broader review of strategy against the Islamic State ordered by Trump and due to be delivered to the White House on Tuesday. Although the focus of the review is on ways to speed up the fight against the Islamic State, there is a recognition, U.S. officials said, that the war against the militants cannot be won without also addressing the wider Syrian conflict.

“We do need to have a vision of how our military actions set conditions on the ground that actually then become the platform from which Secretary [of State Rex] Tillerson goes to Geneva to come up with a political solution,” Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff, told a forum at the Brookings Institution last week.

Whether a political settlement is even possible, given the current circumstances on the battlefield, is in question, however, analysts said. Russia’s intervention and the government’s victory in Aleppo decisively tilted the balance in favor of Assad, who is now in no danger of being toppled militarily by the rebels.

“Logically speaking, why would the regime give up something in Geneva that the armed opposition failed to gain militarily on the ground?” said Jihad Makdissi, who leads a separate opposition organization called the Cairo Group. “The word ‘concession’ is not now in the dictionary of the regime’s mind. As long as the regime can’t manage to get international recognition again, why would they give concessions?”

Given the obstacles, de Mistura, the U.N. envoy, set expectations low as he opened the talks last week, telling journalists that he anticipated no breakthrough.

“The Geneva talks seem to be something that everyone wants because they want to have talks,” said Aron Lund, a fellow at the U.S.-based Century Foundation think tank. “But no one really knows what they are going to say.”

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