Syrian rebels reportedly control most of Aleppo following their surprise offensive which left regime forces reeling.
Thousands of opposition fighters in armoured vehicles have been deployed to landmarks in the country’s second-largest city, including the old citadel, said residents.
It comes a day after the rebels entered Aleppo where they reportedly faced little resistance from pro-government troops.
The insurgents, led by the Islamist militant group Hayat Tahrir al Sham and including Turkey-backed fighters, also claim to be in control of all of Idlib province after launching their offensive on Wednesday.
Russian and Syrian jets have responded by bombing the rebels as they contend with the most serious challenge to President Bashar al Assad in many years.
Witnesses said two airstrikes on the edge of Aleppo targeted insurgent reinforcements and hit near residential areas.
At least 300 militants have been “eliminated” in the past 24 hours in missile and bomb attacks by the Syrian army and Russian air forces on command posts, warehouses, and artillery positions, according to Russia’s ministry of defence.
Syria’s military said it had carried out a “temporary troop withdrawal” in Aleppo to prepare for a counteroffensive against “terrorists”.
And it admitted insurgents had entered large parts of the city but said they had not set up bases or checkpoints.
President remains defiant
Mr Assad said his country will continue to “defend its stability and territorial integrity against terrorists and their supporters” and the regime was able to defeat them no matter how much their attacks intensify.
The rebels have seized Aleppo international airport, according to a war monitor, the UK-based Syrian Observatory for Human Rights (SOHR).
The insurgents have also taken control of several cities and towns in the northern Hama countryside amid the “withdrawal and breakdown of the regime”, SOHR claimed.
But the Syrian ministry of defence denied the reports, saying there was “no truth” to them.
The rebels claimed on Saturday evening to have also entered the city of Hama.
‘Dangerous situations’
Meanwhile, the Russian defence ministry criticised the US-led coalition – which includes the UK – for creating “dangerous situations” after its fighter jets “violated” Syria’s airspace.
It said: “In the area of the Al Tanf city, 12 violations… have been recorded over the past 24 hours: a pair of F-15 fighters (four times), a pair of Typhoon fighters, and a pair of A-10 attack aircraft.”
Such actions run the risk of “dangerous preconditions for aviation incidents and accidents”, the ministry warned.
Fierce battles
Dozens of Syrian soldiers have been killed in fierce battles in Aleppo and Idlib in the past few days, the military has said.
Russia, one of Mr Assad’s key allies, has promised Damascus extra military aid to thwart the rebels, two military sources told the Reuters news agency.
Syrian rebels take flag from monument
Iranian condemnation
And Iran’s foreign ministry has condemned what it called “aggression by terrorist elements” against its Aleppo consulate during the rebel advances, its state media reported.
Iran and Russia have voiced support for Syria and the Iranian foreign minister was due to visit Damascus on Sunday.
Also, a UN official has hit out at the violence, saying “relentless attacks” over the past three days in northwestern Syria have killed 27 civilians, including eight children.
And the attacks have now returned to Aleppo for the first time since 2016, when President Assad and his allies Russia, Iran, and regional Shia militias retook it.
‘Like an earthquake’
Charles Lister, Syria programme director at the Middle East Institute, told Sky News: “To see the entire city fall in 24 hours as we did on Friday is beyond dramatic, it’s like an earthquake in the scale of the last 13-14 years of the Syrian crisis.”
The opposition fighters have said the campaign is in response to increased strikes in recent weeks against civilians by the Russian and Syrian air forces on areas in rebel-held Idlib.
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Rebel offensive expanded
Turkey said its diplomatic efforts had failed to stop the government attacks on opposition-held areas, which were in violation of a de-escalation deal sponsored by Russia, Iran and Ankara.
Turkish security officials said a limited offensive by the rebels was planned to stop government attacks and allow civilians to return, but the assault expanded as Syrian government forces retreated.
Insurgents have posted videos online showing themselves using drones in their advance for the first time. It is not clear to what extent they were used on the battlefield.
It had appeared to be a conflict frozen in time, but the operation launched with blistering speed by Syrian opposition fighters has turned all of that upside down.
It is also a potent reminder of the complexity of the Syrian conflict.
What was a stalemate has revealed that the regime of President Bashar al Assad may very well be standing on clay feet.
Whether the rebel push continues its momentum and transforms into a wider offensive remains to be seen – but its significance politically and militarily is immense.
