Rebel forces pressing a lightning offensive in Syria aim to overthrow President Bashar al-Assad's rule, their Islamist leader said in an interview published on Friday.
The Islamist-led rebels were at the gates of Syria's Homs, a war monitor said, after wresting other key cities from government control.
In little over a week, the offensive has seen Syria's second city Aleppo and strategically located Hama fall from President Bashar al-Assad's control for the first time since the civil war began in 2011.
Should the rebels capture Homs, that would cut the seat of power in the capital Damascus from the Mediterranean coast, a key bastion of the Assad clan.
By Friday morning, the rebels were just five kilometres (three miles) from the edge of Homs, according to the Syrian Observatory for Human Rights monitor.
Abu Mohammed al-Jolani, the leader of the Hayat Tahrir al-Sham (HTS) rebel alliance, said the goal of the offensive was to overthrow Assad's rule.
"When we talk about objectives, the goal of the revolution remains the overthrow of this regime. It is our right to use all available means to achieve that goal," Jolani told CNN in an interview.
The rebel alliance conducting the offensive that began on November 27 is led by HTS, which is rooted in the Syrian branch of Al-Qaeda but has sought to moderate its image in recent years.
Fearing the rebels' advance, tens of thousands of members of Assad's Alawite minority were fleeing Homs on Thursday, residents and the Observatory said.
Khaled, who lives on the city's outskirts, told AFP that "the road leading to (coastal) Tartus province was glowing... due to the lights of hundreds of cars on their way out".
Homs was the scene of a months-long government siege of opposition areas and deadly sectarian attacks in the early years of the civil war.
Early in the war, which began with Assad's brutal crackdown on democracy protests, activists referred to the city as "the capital of the revolution" against the government.
Haidar, 37, who lives in an Alawite-majority neighbourhood, told AFP by telephone that "fear is the umbrella that covers Homs now".
"I've never seen this scene in my life. We are extremely afraid, we don't know what is happening."
After the government lost control of Aleppo and Hama, air strikes targeted a bridge on the highway linking Hama and Homs, the Observatory said.
But on Friday, the rebel alliance "entered the cities of Rastan and Talbisseh" on the main road between Hama and Homs, the monitor added, saying that the factions were faced with "a total absence" of government forces.
The Syrian defence ministry said the army launched strikes against "terrorist" fighters in Hama province.
The Observatory, which relies on a network of sources in Syria, said 826 people, mostly combatants but also including 111 civilians, have been killed since the offensive began last week.
The United Nations said that the violence has displaced 280,000 people, warning that numbers could swell to 1.5 million.
Many of the scenes witnessed in recent days would have been unimaginable earlier in the war.
The rebels announced on Telegram their capture of Hama following street battles with government forces, describing it as "the complete liberation of the city".
Rebel fighters kissed the ground and let off volleys of celebratory gunfire as they entered the city on Thursday.
Many residents turned out to welcome the rebel fighters. An AFP photographer saw some residents set fire to a giant poster of Assad on the facade of city hall.
The army admitted losing control of the city, though Defence Minister Ali Abbas insisted that the army's withdrawal was a "temporary tactical measure".
In a video posted online, HTS leader Jolani said his fighters had entered Hama to "cleanse the wound that has endured in Syria for 40 years".
He was referring to an army massacre in Hama in the 1980s that targeted people accused of belonging to the banned Muslim Brotherhood.
In another message on Telegram congratulating "the people of Hama on their victory," he used his real name, Ahmed al-Sharaa, instead of his nom de guerre for the first time.
Aron Lund, a fellow of the Century International think tank, called the loss of Hama "a massive, massive blow to the Syrian government".
Should Assad lose Homs, it wouldn't mean the end of his rule, Lund said.
"But at that point, without Aleppo, Hama or Homs, and with no secure route from Damascus to the coast, I'd say it's over as a credible state entity," he added.
UN chief Antonio Guterres said Thursday that the escalation in Syria is the result of a "chronic collective failure" of diplomacy.
The rebels launched their offensive in northern Syria the same day a ceasefire took effect in the war between Israel and Hezbollah in neighbouring Lebanon.
Israel's army said Friday it had conducted air strikes on Hezbollah "weapon-smuggling routes" on the Syria-Lebanon border, just over a week into the fragile ceasefire in their war.
