A gruesome video has emerged out of Syria that shows US-backed Turkey's proxy militia with Al Qaeda alliance beheading bodies of Assad soldiers.

Turkey, a NATO ally, has been engaged in a bloody battle, in what Ankara claims is an effort to bring peace in Syria against Assad oppression.

The mobile phone footage that has surfaced online shows the Turkish-backed forces committing war crimes, with acts of brutality. Neither Ankara nor NATO has issued any statement.

In the video, a bearded man can be heard chanting "Allahu Akbar" as he proceeds to cut off the head of a Pro-Assad Syrian soldier, while issues threats to all those who support the Syrian regime.

The gruesome footage is much like that produced by the ultra-violent Islamic State (ISIS) group. Only in this instance, it was filmed by proxy militants from Hayat Tahrir al-Sham, a rebranded affiliate of Al-Qaeda — and that Turkey, with US backing, is supporting in its war against the Syrian regime.

The video was filmed on February 20 in Neirab, a town in Idlib province's west recently captured by forces loyal to President Bashar al-Assad.

Since then the militia group has pushed in to recapture the town and it is believed that they were being supported by Turkish commandos.

Turkey, a NATO ally, now has requested the US to deploy two Patriot missile-defense batteries on its southern border to free it to punish any future attacks by Russian-backed Syrian troops, according to a senior Turkish official in Ankara.

According to Turkish officials, it could use F-16 warplanes to strike units loyal to Assad in Idlib if the Patriots were deployed in Hatay on Turkey's border to provide protection.

Idlib is facing a humanitarian disaster as hundreds of thousands flee a Syrian and Russian military campaign to retake the province from militant rule.

Overlooked in Western coverage of the crisis is that Idlib is mostly controlled by Hayat Tahrir al-Sham, a rebranded affiliate of Al-Qaeda — and that Turkey, with U.S. backing, has intervened to keep the extremist group in place.

Earlier this month, the proxy militants earlier were seen in a video dragging the bodies of dead Syrian pilots tied to a motorcycle. The pilots were killed after their Russian-made Mi-17 helicopter was shot down by militants during a military campaign in Idlib.