Beirut: A Kurdish militia that has been fighting Daesh in Syria with help from US-led air strikes has joined forces with Arab groups in an alliance announced on Monday that may be a prelude to an attack on the terrorists’ base of operations in Raqqa.

The alliance calling itself the Democratic Forces of Syria includes the Kurdish YPG militia and Syrian Arab groups, some of which fought alongside it in a campaign that drove Daesh from wide areas of northern Syria earlier this year.

The Arab groups in the new alliance are operating under the name “The Syrian Arab Coalition” - a grouping which US officials have said would receive support under a new US strategy aimed at fighting Daesh in Syria.

A US military official has said that the Syrian Arab Coalition would push down towards Raqqa, Daesh’s de facto capital, while staying east of the Euphrates river.

Keeping the YPG-backed force east of the river could ease Turkish concerns about any further expansion of Kurdish influence in northern Syria. Turkey is worried about the Kurds’ growing power in Syria fuelling separatism among its own Kurds.

The United States last week announced a shake-up of its support to Syrian rebels fighting Daesh, effectively ending its programme to train fighters outside Syria and focusing instead on providing weapons to groups whose commanders have been US-vetted.

The YPG has to date proved the most effective partner on the ground for US-led air strikes against Daesh. By deepening ties with groups from Syria’s Arab majority, it could deflect concern among some Arabs that it exists solely to fight for the interests of Kurds.

The YPG drove deep into Raqqa province earlier this year, but stopped short of advancing on Daesh’s de facto capital of Raqqa city, saying it wanted Syrian Arab rebels to lead such an assault.

The new alliance includes the YPG, various Arab groups including Jaysh Al Thuwwar (Army of Revolutionaries) and the Arab tribal Jaysh Al Sanadeed, and an Assyrian Christian group, according to a statement announcing its establishment.

“The sensitive stage our country Syria is going through and rapid developments on the military and political front... require that there be a united national military force for all Syrians, joining Kurds, Arabs, Syriacs and other groups,” said the statement, which was sent by a YPG spokesman.

“Given that these forces in general are democratic and secular forces that believe to a great degree in diversity, we hope that they will receive support” from the US-led coalition, said Nasir Haj Mansour, an official in the defence ministry of the Kurdish administration in YPG-held territory.

“The current goal in practical terms is to confront [Daesh], given that it is the first enemy, but the goal is also to build a democratic Syria in the future,” he said by telephone.