KURDISH militia said they were fighting Isis terrorists on the south side of Syria’s biggest hydroelectric dam yesterday.

Syrian Democratic Forces (SDF) spokeswoman Cihan Sheikh Ehmed said her forces were at the southern entrance of the Tabqa dam complex on the Euphrates River.

US helicopters airlifted SDF guerillas — mainly consisting of the Kurdish YPG militia — across Lake Assad upstream from the dam on Tuesday.

The United States now has at least 700 troops in Syria against the will of President Bashar al-Assad’s government.

Many locals fear Isis will blow up the dam, which generates 800MW of power, rather than surrender it to their enemies.

French Defence Minister Yves Le Drian — whose country also has troops in Syria — said the offensive to capture the Isis stronghold of Raqqa to the east of Tabqa would begin within days.

At UN-brokered peace talks with Western-backed insurgent factions in Geneva, Syrian UN ambassador Bashar al-Jaafari reiterated that foreign action without his government’s permission was “illegitimate.”

“Those who are truly fighting Daesh [Isis] are the Syrian Army with the help of our allies from Russia and Iran,” he insisted.

Meanwhile the Syrian army surrounded and destroyed a force of al-Qaidaled Hayat Tahrir as-Sham (Hetesh) extremists who invaded the town of Qamhana, just three miles northwest of the central city of Hama.