The Nusra Front has announced it will renew its assault on the Syrian government and claimed the "defeat" of Russian forces after Moscow ordered a partial pullout from the country.

The al-Qaeda affiliate said on Tuesday: "It is clear that Russia has suffered defeat, and within the next 48 hours Nusra will launch an offensive in Syria.

"The Russians withdrew for one reason, and it is because while they were backing the regime, the regime was unable to hold onto the territories that it took over," a Nusra commander told the AFP news agency.

"Had it not been for the Russian warplanes, we would have been in Latakia," he said, referring to the provincial capital of the heartland of President Bashar al-Assad's Alawite community.

"The (Syrian) army let down the Russians. It is a cowardly army," he said.

Russia, he said, "will not make any more sacrifices for a regime that has basically collapsed."

Unlike the Islamic State group - who splintered from al-Qaeda in 2014 - Nusra has embedded itself within the Syrian opposition and dedicated itself primarily to the overthrow of the government of Bashar al-Assad.

However, following the declaration of a ceasefire in Syria on 27 February - which excluded both Nusra and IS - there had been rumours of popular resentment building against the group.

On Sunday clashes broke out in the Idlib town of Maarat al-Numan, after Nusra clamped down on demonstrations against the group by civilians there and drove out the Free Syrian Army 13th Division from the town.

By Monday, however, more protesters had taken to the streets and reportedly ransacked a Nusra headquarters.

Nusra released a statement on Monday condemning what it called "seditious religious officials" who had criticised the group and called for the matter to be referred to a Sharia court.

"Nusra invites all of its members to practice self-control and exercise the highest degree of patience, as the greatest beneficiaries of any clash during this period are the Nusayri (Alawite) regime and its allies," the statement added.

Some analysts have seen the unrest as a sign that the grip of al-Qaeda in parts of opposition-held Syria could potentially be slipping.

“For the first time in Syria’s revolution, al-Qaeda appears to have overstepped the mark, provoking a genuinely popular backlash against its increasingly domineering role in the conflict,” wrote Charles Lister, Resident Fellow at the Middle East Institute.

“With international attention focused on the initiation of peace talks in Geneva, this invaluable opportunity to expose al-Qaeda’s malign intentions in Syria should not be missed.”

Following the beginning of the ceasefire there had been reports that Nusra had been withdrawing from towns in Idlib to prevent becoming targets for Russian bombing raids.

Residents in the town of Atareb in Aleppo also reportedly told Nusra to “get out” of their town, fearing air strikes.

Despite the announcement on Monday that it would be pulling out of Syria, Russian air strikes were continuing on Tuesday, reportedly striking IS targets in Palmyra.

A deputy defence minister on Tuesday said that Russia would continue to strike "terrorist targets" in the country despite the pullout.

"It is still too early to speak of victory over terrorism. The Russian air group has a task of continuing to strike terrorist targets," deputy defence minister Nikolai Pankov was quoted as saying by Russian news agencies.