Clashes erupted between ISIL and Nusra Front fighters near the border with Lebanon Friday, after gunmen rejected an attempt by the latter to unite the opposition in Syria's Qalamoun region under a single leader.

The clashes were concentrated on the outskirts of the Syrian village of Ras al-Maara, a source close to the Nusra Front told The Daily Star. Ras al-Maara is a few kilometers from Lebanon's northeastern town of Arsal, the scene of ongoing clashes between the Lebanese Army and the two jihadi groups.

Nusra, Al-Qaeda's official affiliate in Syria, has had an on-again, off-again relationship with ISIS since the two had a falling out last year over chain of command when ISIL's current leader Abu Bakr al-Baghdadi tried to absorb Nusra.

The group under the command of the Nusra Front leader in Qalamoun, Abu Malek al-Talli, engaged in fighting with ISIL gunmen there.

Media reports identified the ISIL branch as the Abi Abdel-Salam group.

Speaking on condition of anonymity, the source said the Nusra Front, under Talli, sought to unite opposition groups in the Qalamoun region under a single umbrella to better confront Syrian army troops and their allies, including Hezbollah.

There are around 18 separate groups based in Qalamoun, fighting on separate fronts.

ISIL-affiliated groups based near the border with Lebanon have rejected the proposal, saying that they wanted to preserve the few smuggling routes left in some areas to themselves, the source said.

ISIL and the Nusra Front cooperated against the Lebanese Army during clashes in Arsal earlier this year and took dozens of policemen and soldiers hostage.

Talli's group is holding the Lebanese policemen on the outskirts of Arsal.

By Nidal Solh