Beirut: Syria's Army announced Thursday a "vast offensive" to wrest back territory from armed opposition groups, as NATO voiced alarm at escalating Russian military activity in the war-torn country.
Moscow has dramatically stepped up its nine-day-old air war against opponents of President Bashar al-Assad, with heavy bombing by warplanes and cruise missile strikes from the Caspian Sea.
A Syrian general said the Russian intervention had weakened the Islamic State (IS) jihadist group and other armed opponents of Assad.
But according to Washington, more than 90 per cent of Russia's strikes have targeted the moderate opposition.
NATO Secretary General Jens Stoltenberg said there had been a "troubling escalation" in Moscow's air campaign.
"We will assess the latest developments and their implications for the security of the alliance," Stoltenberg said as he went into a NATO defence ministers meeting in Brussels dominated by the Syrian conflict.
"This is particularly relevant in view of the recent violations of NATO's airspace by Russian aircraft," he added.
Tensions between Russia and NATO member Turkey shot up this week after Russian aircraft infringed on Turkish airspace at least twice.
The Russian air war has provided cover for Assad's ground troops, who have previously lost swathes of the country to IS and other fighters seeking to topple him.
The Syrian army's chief of staff, General Ali Abdullah Ayoub, announced today "a vast offensive to defeat the terrorist groups" and restore army control over opposition-held areas.
He did not specify where the operation would take place, but said Russian air strikes had helped "weaken the fighting capabilities of Daesh and other terrorist groups," using the Arabic acronym for IS.
Quoted by Syrian state television, Ayoub said the strikes had helped Syria's armed forces "maintain the military initiative".
Moscow carried out new air raids today on Assad's coastal heartland of Latakia as well as the central province of Hama and near the northwestern city of Idlib, according to a monitoring group.
Russian bombardment came in support of a ground assault by Syrian troops and allied militia seeking to push rebels back from the Sahl al-Ghab plain in Hama, the Syrian Observatory for Human Rights said.
The plain, which borders Latakia, has been the focus of a months-long offensive by a rebel alliance including Al-Qaeda's Syria affiliate Al-Nusra Front.