The withdrawal of US troops from northeast Syria and a series of undisclosed deals brokered by Russia have triggered a scramble for the key city of Manbij, potentially pitting Turkish forces and its allied armed groups against forces loyal to the regime of President Bashar al-Assad.

Manbij – a commercial hub within a largely agricultural area – lies west of the Euphrates River and falls adjacent to the Turkish border as well as the main M4 highway coursing through northern Syria. It was once designated the capital for a proposed new Syrian province encompassing rural Aleppo, and has long been coveted by the region’s largely ethnic Arab population.

Holding the city represents a strategic victory, says Omer Ozkizilcik, a Syria expert at Seta, an Ankara-based think tank.

“The importance of Manbij has to do with its large population [about 300,000] and its strategic location on the M4 highway.

“Whoever controls the area of Manbij controls the logistics supply route from Iraq to Aleppo. This means having huge financial and military superiority,” says Mr Ozkizilcik.

Turkey launches offensive into Syria Show all 25 1 /25 Turkey launches offensive into Syria Turkey launches offensive into Syria Turkish soldiers with armored vehicles EPA Turkey launches offensive into Syria A woman flees with her children during Turkish bombardment on Syria's northeastern town of Ras al-Ain AFP/Getty Turkey launches offensive into Syria Smoke billows following Turkish bombardment on Syria's northeastern town of Ras al-Ain in the Hasakeh province along the Turkish border on October 9, 2019. - Turkey launched an assault on Kurdish forces in northern Syria with air strikes and explosions reported along the border. President Recep Tayyip Erdogan announced the start of the attack on Twitter, labelling it "Operation Peace Spring". (Photo by Delil SOULEIMAN / AFP) (Photo by DELIL SOULEIMAN/AFP via Getty Images) DELIL SOULEIMAN AFP/Getty Turkey launches offensive into Syria The first group of Turkish infantry prepare to enter Syria on the border Getty Turkey launches offensive into Syria Civilians flee AFP/Getty Turkey launches offensive into Syria Smoke billows from targets inside Syria AP Turkey launches offensive into Syria Turkish armoured vehicles enter Syria in Akcakale Getty Turkey launches offensive into Syria Civilians leave as smoke rises from Ras al-Ain AFP Turkey launches offensive into Syria A multi-rocket launcher fires in an unknown location Turkish Defence Ministry via Reuters Turkey launches offensive into Syria People wave as Turkish soldiers prepare to cross the border Getty Turkey launches offensive into Syria Girls stand together in Ras al Ain town Reuters Turkey launches offensive into Syria A woman walks as smoke billows following Turkish bombardment in Syria's northeastern town of Ras al-Ain AFP/Getty Turkey launches offensive into Syria A Turkish army's tank drives down from a truck towards the border with Syria AFP/Getty Turkey launches offensive into Syria Turkish jet taxis on tarmac after returning to a military base in southeast Diyarbakir Reuters Turkey launches offensive into Syria A Turkish armored vehicle drives down a road during a military operation in Kurdish areas of northern Syria EPA Turkey launches offensive into Syria People sit on belongings at a back of a truck as they flee Ras al Ain town Reuters Turkey launches offensive into Syria Turkey-backed Syrian opposition fighters enter Tel Abyad AFP/Getty Turkey launches offensive into Syria Civilians flee AFP/Getty Turkey launches offensive into Syria People flee Tal Abyad North Press Agency/Reuters TV Turkey launches offensive into Syria People wave as Turkish soldiers prepare to cross the border into Syria Getty Turkey launches offensive into Syria Civilians flee with their belongings AFP/Getty Turkey launches offensive into Syria Civilians flee during Turkish bombardment on Syria's northeastern town of Ras al-Ain in the Hasakeh province along the Turkish border on October 9, 2019. - Turkey launched a broad assault on Kurdish-controlled areas in northeastern Syria today, with intensive bombardment paving the way for an invasion made possible by the withdrawal of US troops. (Photo by Delil SOULEIMAN / AFP) (Photo by DELIL SOULEIMAN/AFP via Getty Images) DELIL SOULEIMAN AFP/Getty Turkey launches offensive into Syria Turkish President Recep Tayyip Erdogan, right, speaks with Defense Minister Hulusi Akar, left, as they watch the operation by Turkish forces in Kurdish areas EPA Turkey launches offensive into Syria Smoke rises from the Syrian town of Tal Abyad AFP/Getty Turkey launches offensive into Syria Turkey-backed members of Syrian National Army prepare for moving to Turkey with heavy armed vehicles EPA

After receiving what it described as a green light from President Donald Trump, Turkey last week launched “Operation Peace Spring”, a military offensive to establish a 32-kilometre wide (20 miles) buffer zone on the Syrian side of its southern border.

The military intervention and subsequent counter-attacks have left scores dead on both sides of the border, displaced over 100,000 people, and ultimately prompted the Kurdish-led organisation that controls the area to strike a deal with the Assad regime to grant control of its borders to pro-Damascus forces.

Inside Akcakale, a staging ground for the war along the Turkish border, residents were still recovering from the damage of several rockets that struck the city from Syria in a counteroffensive. Plumes of smoke rose from within Syria, where Turkish artillery and aircraft were targetting positions of the Kurdish-led militia.

“It’s a shame what happened here,” says Salih Mehmet, a 46-year-old resident of a neighbourhood where a missile struck the second storey of a house.

Russia, which has emerged as the primary power broker in Syria amid a pullback by the US, appeared at the centre of a tangle of secret backroom deals.

It has been negotiating with Turkey as part of a series of talks about Syria’s future involving Moscow, Ankara and Tehran, guiding the regime in Damascus, and also continuing to maintain ties to the Kurdish-led Syrian Democratic Force (SDF), which has controlled Syria’s northeast since the collapse of regime authority there in 2013.

But it remains unclear how much leeway Moscow has granted any of its three patrons, setting up a confusing and potentially dangerous crisscrossing of interests and armed groups over Manbij and other cities.

Video distributed online appeared to show scenes of Syrian regime forces on the move, heading northward to take up border positions in both Manbij and the northern town of Kobane.

But Turkish armed forces, after taking control of the towns of Ras al-Ain and Tal Abyad, were also on the move towards Manbij, Turkish media outlets reported, with broadcasting footage said to show Turkish armed forces and allied Syrian armed groups inside Manbij

Attempting to project an air of calm, Turkish president Recep Tayyip Erdogan said he was undisturbed by the reports of Syrian regime forces moving towards the city.

“Our Arab brothers, the tribes who are the actual owners of the city, will return once Manbij is cleared,” he told reporters at a press conference on Monday morning. “There are many rumours, but it looks like there won’t be a problem. On the Manbij issue we’re at the stage of implementing our own decision.”

Syrian Arab civilians flee as Turkish troops with American-made M60 tanks and Turkish-backed Syrian fighters gather near the village of Qirata on the outskirts of the northern city of Manbij near the Turkish border on Monday (AFP via Getty Images)

Manbij is the largest city of Aleppo province after Aleppo itself and serves as the bridge connecting the eastern Euphrates area to Aleppo. It includes Syria’s second-largest dam, and is the resting place of Suleyman Shah, the father of the founder of the Ottoman Empire.

“We are most worried about Manbij,” says Wissam Zarqa, a Syrian opposition activist originally from Aleppo, but who has relatives in Manbij, who is now a professor at Ankara’s Beyazit Yildirim University.

“It seems now that the Syrian regime and the Free Syrian Army will both try to enter the city, and that will create problems for the city.”

Syria’s armed forces are no match for Turkey. The Syrian Arab Army is badly depleted after nearly nine years of civil war, prompted by an armed popular uprising against the Assad dictatorship. Virtually all of its significant battlefield victories are credited to Russian air power and highly motivated Iranian-backed militias, including Lebanese Hezbollah.

Meanwhile, Turkey has the second-largest land force in Nato as well as a modern fleet of armoured vehicles, supported by advanced fighter jets, artillery and tanks. It has already seized control of swaths of Syria’s northwest. In Akcakale, fighters of the Syrian National Army, the Turkey-backed Arab irregular armed force made of remnants of the rebel units that fought against the Assad regime, could be seen positioning themselves along the border.

We are most worried about Manbij. It seems now that the Syrian regime and the Free Syrian Army will both try to enter the city, and that will create problems for the city Wissam Zarqa, Syrian opposition activist

But geopolitical considerations may hamper Turkey’s quest to seize control of Manbij. Russia controls much of Syria’s skies. Although Mr Erdogan hinted that Moscow had approved Turkey’s push to take both Manbij and Kobane; the Kremlin has long sought to broker a deal between the regime and the Kurds.

On Monday, Mr Erdogan also referred to a previous deal between Turkey and the US for the SDF to leave Manbij and hand it to local allies. That deal was never honoured, Turkey insists, becoming a source of friction between Washington and Ankara.

The murky, evolving dangers on the ground were cited by Trump administration officials as being behind the decision to pull all remaining US troops out of northeast Syria, including from an outpost in Manbij.