Al-Nusra Front fighter in Syria
Al-Nusra Front fighter in Syria Reuters

Rebels backed by Syria's Al-Qaeda affiliate, the Al-Nusra Front, on Wednesday seized control of the last border crossing with Jordan that had been under the control of the Damascus regime, a monitor said, according to AFP.

"Armed groups, joined today by Al-Qaeda affiliate Al-Nusra Front, took over the Nasib border point from regime soldiers" on the Syrian side of the frontier, said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights.

Abdel Rahman added that regime troops had withdrawn from Nasib, leaving no Syrian government presence along the entire border with Jordan.

There was no immediate information on any casualties. The Jordanian government had said earlier that it had closed the crossing on its side of the frontier to both travellers and goods, noted AFP.

Earlier this week, the Al-Nusra Front  seized the city of Idlib, the second provincial capital to fall from government control.

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 President Bashar Al-Assad's regime, the group has clashed with Western-backed rebels and its jihadist rival the Islamic State (ISIS) group. Last November, Al-Nusra and ISIS agreed to work together.

Al-Nusra Front recently reaffirmed its allegiance to Al-Qaeda and denied any plan to break away and become a more internationally acceptable rebel force, amid speculations on Internet social networks of a split between the jihadist allies.