By Suleiman Al-Khalidi
AMMAN (Reuters) - Syrian rebels battled government forces and allied militia on Wednesday in villages north and east of Hama, a major city whose capture would pile pressure on President Bashar al-Assad.
The rebels have staged their biggest advance in years over the past week, seizing Aleppo - Syria's biggest city before the war - in a lightning assault that has upended long stable frontlines and further destabilised a region already ablaze from war in Gaza.
On Wednesday, as the insurgents mounted fresh assaults around the outskirts of Hama, the most powerful rebel commander was shown on video touring Aleppo's ancient citadel, historically a potent symbol of rule over northern Syria.
Abu Mohammed al-Golani, head of Hayat Tahrir al-Sham (HTS) which was formerly an al Qaeda affiliate, was shown marching out of the citadel's medieval gateway amid cheering supporters and escorted by masked fighters waving opposition flags.
It was a symbolic moment at a site where government forces had hung portraits of Assad when they captured the city in 2016 after a long siege, a major turning point in the war.
The loss of Aleppo last week has stunned Assad and his Iranian and Russian allies, with rebels rapidly taking a swathe of countryside around the city and pushing on to the outskirts of Hama on the road to Damascus.
U.N. Syria envoy Geir Pedersen warned the Security Council on Tuesday that the situation was "extremely fluid and dangerous", adding that Syria faced danger of "further division, deterioration, and destruction".
Syria's civil war killed hundreds of thousands of people, sent many millions fleeing across borders and drew in regional and global powers after erupting in 2011 in a rebellion against Assad.
Syrian state media and rebels said there was fighting on Wednesday around al-Uwayr and neighbouring villages after pro-government forces had pushed back an assault overnight on Jabal Zain al-Abidin, just north of Hama.
Fighting in Uwayr would indicate rebels were advancing into areas of countryside on the eastern flank of Hama, which is one of Syria's most important cities and has stayed in government hands throughout the conflict.
ALLIES
Moscow and Tehran, distracted by conflicts in Ukraine and elsewhere in the Middle East, have scrambled to get more support to Assad, with Russia intensifying air strikes and Iran-backed Iraqi and Afghan militia groups heading to front lines.
Moscow and Tehran have been allies of the Assad dynasty for decades and Syria remains important to both. Assad represents an important link in the network of Shi'ite groups Iran backs across the region. Russia operates a Mediterranean naval port at Tartous and has an air base at Hmeimim near Latakia.
Russian air power and Iran's network of regional militias were vital to Damascus clawing back most of the country from 2015-20 after losing swathes of territory to rebels in the war's early years.
Rebels and Syrian military sources both cited a combination of air strikes and the arrival of reinforcements as crucial in staving off an insurgent approach into northern Hama late on Tuesday.
Iran said on Tuesday it would consider sending forces if asked, and Russia said it would strongly support efforts to "counter terrorist groups and restore constitutional order".
Meanwhile Assad has started a new conscription push, announcing a 50% increase in military pay and setting up checkpoints in Damascus and eastern Deir al-Zor signing up young men to join the army, residents said.
Syrian state media reported further arrivals of reinforcements to Hama on Wednesday.
REBELS
Golani's appearance in Aleppo underscores the growing sway of HTS, long the most powerful faction in northwest Syria, regarded not only by Damascus and its allies but also by Western countries as a terrorist group.
HTS was originally called the Nusra Front as the main al Qaeda franchise in Syria before cutting formal ties with the global jihadist network in 2016.
The insurgents' rapid advance over the past week has brought them new territory that they may struggle to govern, with food and fuel shortages already reported in Aleppo.
It has also led to the capture of several Syrian military bases and rebel sources said fleeing government forces had abandoned significant amounts of weapons and equipment, now in insurgent hands.
HTS fights alongside more mainstream rebel factions that are backed by Turkey.
Ankara also supports the Syrian National Army, a separate rebel grouping that holds a strip of territory along the border. It wants to keep Kurdish groups in Syria away from the frontier and to create a haven for Syrian refugees now living in Turkey.
The United States, which still has a small contingent of troops on the ground after intervening to help defeat Islamic State from 2014-2017, supports an alliance led by Syria's main Kurdish armed group.