Syrian President Bashar al-Assad vows to defeat Islamic State as his troops advance against the militants in two crucial provinces. (Reuters)

Syrian President Bashar al-Assad vows to defeat Islamic State as his troops advance against the militants in two crucial provinces. (Reuters)

Syrian President Bashar al-Assad signaled Tuesday that his government intends to escalate military efforts to crush the five-year-old uprising against his rule, saying the bloodshed will not end until he has regained control over all areas of Syria lost to the rebellion.

His tough words came amid indications that Russia is preparing to reengage in the war in support of Assad, almost three months after it threw its support behind a U.S.-backed cease-fire and announced it was withdrawing most of its military from Syria.

The violence has already been ticking up, with government and Russian warplanes conducting air raids over northern Syria in the past week and rebels launching an offensive to recapture territory south of the city of Aleppo. According to the Institute for the Study of War, Russia tripled the number of its airstrikes over a four-day period last week, to levels not seen since before the imposition of the cessation of hostilities in late February.

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Assad’s comments, made in an address to a newly installed parliament in Damascus, suggested that he and his Russian allies are preparing for a full-scale resumption of the war, with Aleppo as their first target.

“As we liberated Tadmur [Palmyra] and before it many areas, we will liberate every inch of Syria from their hands,” he said, referring to the ancient town in central Syria recaptured from the Islamic State militant group in March. “Our only option is victory, otherwise Syria will not survive.”

A peace process launched in Geneva earlier this year has failed, Assad said, blaming the West and its allies. The talks have deadlocked mainly because of disagreements over whether he should remain in power.

“Our war on terrorism will continue not because we like war. They imposed war on us.” Assad said. “The bloodshed won’t end until we root out terrorism, wherever it is.”

He singled out Turkish President Recep Tayyip Erdogan for blame, saying Erdogan had continued to funnel support to “terrorists” in the Aleppo area. Assad has consistently labeled all the armed opponents to his rule as terrorists.

“Aleppo will be the grave where all the dreams and hopes of that butcher will be buried,” he added, referring to Erdogan.

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A full-scale return to war would mean an end also to U.S. hopes for a diplomatic settlement through a tentative partnership with Moscow. The effort has yielded some results, diplomats say, including evidence that Moscow has exerted pressure on the Syrian government to comply with the cease-fire at least in some places and has held back from supporting some of the regime’s recent offensives.

But Moscow has also signaled impatience with what it regards as U.S. intransigence on several key Russian demands. They include a request that the two powers conduct joint airstrikes in Syria and that the United States oblige moderate rebels to disengage from al-Qaeda affiliate Jabhat al-Nusra.

On Monday, Russian Foreign Minister Sergei Lavrov said Russia would step up air support for the government in the Aleppo area in response to an offensive launched mainly by Jabhat al-Nusra to the south of the city.

“What is now happening in Aleppo and around it — we warned the Americans about this in advance,” Lavrov said. “The U.S. knows that we will be providing air support to the Syrian army to prevent territories from being seized by terrorists.”

At the same time, Russia and the Syrian government have stepped up airstrikes to the northwest of Aleppo, effectively severing a key supply route that is the last remaining link between the rebel-held portion of the city and the outside world. Scores of civilians have been killed in the escalation of strikes, which have also targeted Aleppo itself and towns in the nearby province of Idlib.

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