DAMASCUS, Feb. 28 (Xinhua) -- As the Islamic State (IS) group is falling apart in the countryside of Syria's Aleppo province, tension started brewing between Kurdish-led rebels on one side, and Turkish forces and allied Syrian militants on the other side.
The IS group has been the target of the Kurdish-led Syrian Democratic Forces (SDF), the Turkish forces and allied Syrian rebels fighting under the Turkey-backed Euphrates Shield campaign, as well as the Syrian army and allied fighters of Hezbollah and Russian air force in the countryside of Aleppo.
The Turkish-backed rebels and the Syrian army have made sweeping progress against IS in the eastern countryside of Aleppo.
The Turkish forces last week captured the city of al-Bab, the largest IS stronghold near the Turkish borders. They also captured several towns and areas around that key city.
For its side, the Syrian army made a huge advance, stripping IS of over 600 square km of territory in eastern Aleppo countryside and are currently advancing into more areas, as the IS started withdrawing and evacuating its positions there.
The Syrian army reached areas under the SDF control in the northern countryside of Aleppo, splitting areas under IS control in half, meaning that the few remaining IS strongholds in the northern countryside of Aleppo are now separated from those in the southern countryside.
The Syrian forces also reached the southern rim of al-Bab, closing the way before the Turkish forces could advance more.
Now that the Euphrates Shield has achieved the main goal of capturing al-Bab from IS, activist sources said the campaign has almost done.
Still, Ilnur Cevik, an advisor of Turkish President Reccep Tayyip Erdogan, said on Monday that his country has plans to end the military operation in Syria after capturing the city of Manbij, which is under the control of the SDF, the Kurdish-led group that enjoys the backing of the United States.
Cevik said Turkey is setting up a 56-mile (about 90 km) "buffer zone" into Manbij after capturing al-Bab.
"Ankara is trying to regain its presence there," Cevik said. "As soon as Manbij is captured, Turkey will stop its operation in Syria," he said, referring to the Euphrates Shield operation which was launched by Turkey and Syrian opposition on Aug. 24, 2016.
Erdogan also said on Tuesday that the Ankara-backed forces will move toward Manbij to complete the plans as originally planned.
He noted that the Syrian Kurdish YPG militia, which his country deems as a terrorist organization, must be moved out of the eastern bank of the Euphrates River.
He also shunned aside any possibility of cooperation with the SDF, which is led by the YPG, on fighting IS in its stronghold in al-Raqqa city in northern Syria.
Manbij is now controlled by the so-called Manbij Military Council, which is part of the SDF.
Earlier reports said that Washington has agreed with the Turks to let the Kurdish forces out of Manbij, but it doesn't seem the case anymore.
Following the progress in Aleppo countryside, and the near certainty that Ankara was moving toward dislodging the SDF out of Manbij, the U.S.-led anti-terror coalition deployed forces and machines in the vicinity of Manbij on Monday, according to the Syrian Observatory for Human Rights.
Pan-Arab al-Mayadeen said on Tuesday that the top U.S. military commander for the Middle East, Gen. Joseph Votel, made a secret trip to northern Syria on Friday to meet with the Kurdish groups.
The trip was the first such visit under the new U.S. administration.
The report by al-Mayadeen said that Votel has given guarantees to the Kurds that Washington will not include Ankara in the war on IS in al-Raqqa, particularly now that the SDF has announced third phase of their offensive on al-Raqqa, as the group succeeded in recent months to capture some towns in its vicinity, to isolate the city from its countryside as a prelude to wage a major offensive against IS there.
The top U.S. commander also gave the Kurds a pledge that the coalition air force will protect Manbij from no matter what attacker, according to the report.
Observers believed that the Kurdish fighters have emerged as a reliable ground ally to Washington, which tried to recruit other rebel factions in northern Syria in the past, but they failed to be reliable.
The Kurdish forces have proven to be a real power, as the groups have unleashed attacks in al-Raqqa countryside, and recently entered parts of the Deir al-Zour province in eastern Syria to fight IS under the cover of the United States.
The U.S. support to the Kurds has apparently raised the ire of Ankara, which repeatedly urged Washington to drop its backing of the Kurds and arm other Syrian rebel groups instead.
Still, backing the Kurdish presence seemed essential for the new U.S. plan of defeating IS in al-Raqqa.
The United States is now under the pressure of both allies, the rival Kurds and Turks.
Nearly 20,000 Arab fighters joined the Kurdish-led armed group recently, which seemed to be Washington's guarantee to Ankara that the Kurds will not have more influence near the Turkish borders.
Analysts here said that even though the tension is rising, it's not yet clear how such a tension would be materialized on the ground.
"We could see battles between the Turks and the Kurds, but I think the United States will work to stop that from happening, because it would be a big mess in northern Syria," Maher Ihsan, a Syrian journalist and political analyst said.
The Observatory, for its part, said Tuesday it had information that one of the groups participating in the Euphrates Shield, known as Tel Rifat Council, is bracing to unleash a wide-scale offensive in the northern countryside of Aleppo against the SDF and other Kurdish-affiliated groups.
As for the Syrian army, its main backer Russia was said to have advised the Syrian government forces not to engage in battles with the Turkish-backed rebels, according to the Observatory, as battles in al-Bab and the Turkish forces capture of that city seemed as part of an agreement with Moscow.
Cevik, the adviser to Erodgan, said Monday that the country would not have carried out its "successful" operation against IS in al-Bab without Russia's support, especially its aerospace force.
Both Turkey and Russia have recently sponsored two rounds of talks in Astana, and also a nationwide ceasefire in Syria that went into effect last December, and the battle of al-Bab seemed part of the agreement between both powers.
As for the Syrian army and the Kurdish-led groups, battles are not expected to happen between them, as the army's top enmity is focused on Turkey.
On the contrary, possible cooperation is also on the table.
The SDF spokesman, Col. Talal Silo, said on Tuesday that they will not engage in battles against the Syrian forces, which are now close to Manbij.
He pointed out the possible benefits of the Syrian military progress in the eastern countryside of Aleppo, in terms of linking areas under the Kurdish control with the Aleppo city.
Silo also said that opening a road between Aleppo and Manbij would benefit the civilians in terms of merchant movements and transportation.
Bashir Othman, a Syrian journalist, was cited by Kurdish news outlets as saying that what Silo probably meant is that the Kurdish forces could cooperate with the Syrian government army to open the road.