Beirut: Daesh has warned that the Tabqa Dam, which a US-backed Kurdish and Arab militia is trying to capture from the militant group, is at imminent risk of collapse because of air strikes and increased water levels.

It also said in messages carried on its social media channels that the dam’s operations had been put out of service and that all flood gates were closed.

The dam, on the Euphrates about 40 kilometres upstream from Daesh’s stronghold of Raqqa, is the largest in Syria. The US-backed Syrian Democratic Forces has been battling to capture the dam from Daesh since Friday.

A Britain-based war monitor, the Syrian Observatory for Human Rights, said it had also learnt from its own sources that the dam had stopped functioning but that Daesh remained in control of its main operational buildings and turbines.

The dam is about 4km long and the SDF has advanced a small distance along the dam from the northern bank but its progress is slow because Daesh has heavily mined the area, the Observatory said.