Nusra Front jihadist
Nusra Front jihadistReuters

The head of the Syrian rebel group Al-Nusra Front, an offshoot of Al-Qaeda, on Monday urged insurgents to escalate attacks on the strongholds of President Bashar Al-Assad's minority Alawite sect, in retaliation for what he said was the “indiscriminate killing” of Sunnis by invading Russians, Reuters reports.

The audio message from Abu Mohammad al-Golani, posted on YouTube, said Russia's military intervention since last week was aimed at saving Assad's rule from collapse but was doomed to fail, as had previous Iranian and Hezbollah military support.

"There is no choice but to escalate the battle and to target Alawite towns and villages in Latakia and I call on all factions to ... daily hit their villages with hundreds of missiles as they do to Sunni cities and villages," Golani said, according to Reuters.

He describing the Russian intervention as a “new Christian crusade from the east” that was doomed to fail and came after a "string of victories made by the Mujahdeen" threatened Assad's rule.

"The war in Cham (Syria) will make the Russians forget the horrors of what they faced in Afghanistan. The new Russian invasion is the last dart in the weaponry of the enemies of Muslims and the enemies of Syria," he said.

Russia has dramatically intensified its bombing campaign in recent days. While Moscow says it is targeting the Islamic State (ISIS) group, most of its airstrikes have hit other rebel factions fighting against Assad, some of which have the support of Arab powers, Turkey or the United States.

Al-Nusra Front has been an official branch of Al-Qaeda since April 2013, and dominates a swathe of northwest Syria despite months of international airstrikes.

As well as fighting Assad's regime, the group has clashed with Western-backed rebels as well as with its jihadist rival ISIS. Last November, Al-Nusra and ISIS temporarily agreed to work together.

Golani’s comments in the latest video mark a change in position. He previously declared that the group will not target the country's Alawite minority, despite their support for Assad.

“Our war is not a matter of revenge against the Alawites despite the fact that in Islam, they are considered to be heretics, " he said at the time, adding, "Our fight is strictly with those who attacked us and murdered our people."