Abu Mohammad al Golani, the leader of Hayat Tahrir al Sham (HTS), led by the former Syrian offshoot of al Qaeda, said its goal was a unified civilian administration in Idlib that brings stability and ends lawlessness.
"We don't have the aim of ruling the liberated north. We want to hand over all our areas to a civilian government," he told HTS-affiliated Amjad news agency in his first comments since the latest round of infighting.
Last week the jihadist group, listed as terrorists by the United States, Turkey and others, forced factions from the Turkey-backed Free Syrian Army (FSA) to accept a peace deal recognizing civilian control by an HTS-backed administration.
The rise of Hayat Tahrir al Sham has prompted worries by Turkey and the mainstream rebels they support that the latest gains by the hardline Islamists in Idlib region would give Moscow the pretext to renege on a peace deal struck in Sochi in September.
The agreement puts the onus on Turkey to ensure banned Islamist groups are expelled from a frontline buffer zone.
The jihadists have allowed Turkish troops to deploy along the front lines as the Russia-Turkey deal demanded, but have not pulled out of the area.
Golani said southern Syria and Eastern Ghouta had been in the hands of moderate Western-backed groups and not jihadists when the Russians and their Syrian army allies launched devastating military campaigns last year to end opposition control.
"The enemy that strikes children, women and hospitals does not need a excuse to enter an area and hit," Golani said.
"We should not try to justify to the enemy we are kind hearted people who deserve to live in this area, this is war," he said.
Russia on Friday said it remained committed to the agreement it had struck with Turkey to stabilize a de-escalation zone in Idlib, but was worried by an increase in the number of ceasefire violations.Turkish defense minister Hulusi Akar who visited the border area adjoining Idlib along with the chief of general staff and the intelligence agency reassured Russia his country was "making every effort to preserve the ceasefire and stability in Idlib."