Clashes among Syrian rebel groups backed by Turkey ended on Sunday after they agreed to a truce, residents and rebel sources said, easing fears of wider internecine warfare among opponents of President Bashar al Assad's rule.

Rebel negotiators told Reuters that Turkey, which maintains thousands of troops inside northwest Syria, mediated a deal among Failaq al Sham, Levant Front, Jaish al Islam and Ahrar al Sham.

They are part of the Syrian National Army coalition of armed opposition groups backed by Turkey.

At least eight people were killed and scores injured on Saturday in fighting among the factions near al Bab city in northwest Syria's Aleppo province.

The clashes prompted Hayat Tahrir al Sham, the former al Qaeda offshoot, to deploy in areas under the control of its rivals in the Syrian National Army, raising fears it sought to expand beyond the areas they control in Idlib province to the Afrin area.

Under the truce, the factions returned Ahrar al Sham's headquarters and moved back to their prior positions. The accord

ended the spectre of prolonged fighting.[L8N2XO2RD]

The northwest of Syria near the Turkish border is the last part of the country still in the hands of fighters seeking to topple the Syrian president, but control has been divided between jihadist factions and other rebels backed by Turkey.

Ideological differences divide Islamist militants from nationalist groups in the Free Syrian Army that have gathered under the banner of the Syrian National Army, which has the backing of Turkey.

Turkey with the help of the Syrian National Army has carried out four operations in northern Syria since 2016, seizing hundreds of kilometres of land. Rebel commanders say they have stepped up their readiness to back up any new incursion.

The armed opposition has been plagued by infighting since the uprising against Assad began in 2011. Turf wars have helped the Syrian president, with his Iranian and Russian allies, recover much of the territory previously held by rebels.