With the fall of the Islamic State group's last significant stronghold in Syria, Iranian and Russian-backed Syrian troops now turn to face off with their main rival, the US-backed forces holding large oil fields and strategic territory in the country's north and east.
The complicated map puts US and Iranian forces at close proximity, standing just across the Euphrates River from each other, amid multiple hotspots that could turn violent, particularly in the absence of a clear American policy.
There are already signs.
Iran threatened last week that Syrian troops will advance toward Raqqa, the former IS capital, which fell to the U.S.- backed Syrian Democratic Forces in October, raising the potential for a clash there. The Kurdish-led SDF also controls some of Syria's largest oil fields, in the oil-rich eastern Deir el-Zour province, an essential resource that the Syrian government also says it will take back.
The SDF also faces restlessness in an Arab-majority town it liberated last year, a possible sign of things to come in other areas that the Kurdish-dominated forces control in their self-rule area in northern Syria, now about 25 per cent of the country's territory.
The question now is whether the United States is willing to confront the troops of Syrian President Bashar Assad and Iranian-backed militiamen.
The Kurds are seeking a clear American commitment to help them defend their gains. American officials have said little of their plans and objectives in Syria beyond general statements about continuing to deny IS safe havens and continuing to train and equip allies.
During a meeting this week with Ali Akbar Velayati, the adviser of Iran's supreme leader, Assad said his war was against terrorism and against plans to partition Syria, a direct reference to Kurdish aspirations for a recognized autonomous zone in the north. He repeated that his government plans to regain control of all of Syria.
Government victories "have foiled all partition plans and the goals of terrorism and the countries sponsoring it," Assad said.
Meanwhile, four US officials said yesterday the US and Russia are nearing an agreement on Syria for how they hope to resolve the Arab country's civil war once IS is defeated. If clinched, the deal could be announced by President Donald Trump and Russian President Vladimir Putin after a meeting in Vietnam today, they said.
The United States has been reluctant to hold a formal meeting between the leaders unless they have a substantive agreement to announce. The officials weren't authorized to discuss the deliberations and requested anonymity.
With its collapse in Boukamal yesterday, the Islamic State group has no major territory left in Syria or Iraq. Its militants are believed to have pulled back into the desert, east and west of the Euphrates River. The group has a small presence near the capital, Damascus.
The Euphrates now stands as the dividing line between Syrian government troops and the SDF in much of Deir el-Zour province.
Government forces and their allies, including Iranian troops and fighters from the Lebanese militant group Hezbollah, control the western bank. They hold the provincial capital and several small oil fields.
The Kurdish-led force, along with American troops advising them, is on the eastern bank. They hold two of Syria's largest oil fields, nearly a dozen smaller ones, one of the largest gas fields and large parts of the border with Iraq. They say they are determined to keep the government from crossing the river.
Iran's Velayati said the US presence aims to divide Syria. "They have not and will not succeed in Iraq and they will also not succeed in Syria," he said during a visit to Lebanon last weekend.
"We will soon see the Syrian government and popular forces in Syria east of the Euphrates and they will liberate the city of Raqqa."
The US coalition declined to comment on Velayati's remarks, saying "it would not be appropriate to comment on speculation or rumor by any third party."
Washington has been wary of Iran's increasing influence in the area and its attempts to establish a land corridor from Iran across Iraq and Syria to Lebanon. For weeks, the coalition said the SDF intended to push to Boukamal. Now it is not clear what the US will do.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)