State television said army forces, working with pro-regime militia, had seized control of the town of Rabia after heavy fighting with rebels.
It was the second strategic victory for pro-regime forces in Latakia in less than two weeks, after government troops seized the town of Salma from rebels on January 12.
‘In the coming weeks, we will be able to announce that all of Latakia -- city and province -- is free from armed groups,’ a Syrian army commander in Latakia told AFP.
The army would use Rabia as a launching point for ground operations against rebel-held towns to the east in the adjacent Idlib province, he said.
Rabia had been held by the opposition since 2012 and was controlled by a range of rebel groups including some made up of Syrian Turkmen, as well as Al-Qaeda affiliate Al-Nusra Front.
State news agency SANA said government forces were ‘combing the area to dismantle any explosive devices or mines planted by the terrorists’.
It said many rebels had been killed in the fighting but provided no other details.
According to the Syrian Observatory for Human Rights, Rabia fell on Sunday after a regime advance that left the town surrounded.
- Blocking rebel attacks -
‘In the past 48 hours, regime forces surrounded the town from three sides -- the south, west, and north -- by capturing 20 villages,’ Observatory head Rami Abdel Rahman told AFP.
He said senior Russian military officials oversaw the battle and that Russian air strikes ‘played an essential role’ in the fight.
With Rabia's capture, government troops are closing in on rebel supply routes through the Turkish border to the north, he added.
Armed opposition factions have used northern parts of Latakia province to carry out rocket and bomb attacks on the provincial capital along the coast.
Backed by Russian air power, pro-regime forces are chipping away at that territory in a bid to secure the Assad clan's heartland.
Rabia ‘is at the crossroads of supply routes in this region’ leading northwest towards the Turkish border and further east to other rebel strongholds, said Syria analyst Fabrice Balanche.
‘By controlling this road, the Syrian army can block rebel movements towards the south, towards Latakia, and the rebels will have a hard time getting close and firing missiles at the (coastal) airport,’ he added.
Russia's air force has operated out of the Hmeimim military airport in Latakia province since September 30.
The regime's latest advance came as world powers intensify efforts to reach a political solution to Syria's war.
Representatives of the government and opposition are set to meet in Geneva this week as part of a UN-endorsed 18-month peace plan.
But sharp disagreements over the makeup of the opposition delegation -- namely, the inclusion of armed groups among negotiators -- have slowed momentum.
- Dispute over opposition -
On Sunday, German Foreign Minister Frank-Walter Steinmeier said upcoming talks should include Islamist rebels, though not ‘terrorists and Islamic extremists’.
‘Where do you expect to find moderate groups after more than five years of civil war, extreme violence and spreading brutalisation?’ Steinmeier was quoted as telling the newspaper Frankfurter Allgemeine Sonntagszeitung.
‘I'm afraid we are past the point where we can really pick and choose all counterparts and negotiators,’ Steinmeier said.
The High Negotiations Committee, a Riyadh-based alliance of opposition groups including the National Coalition, has already announced three delegates it will send to Geneva.
But it came under fire for naming Mohamed Alloush from the powerful rebel group Jaish al-Islam (Army of Islam) as chief negotiator.
Syria's government regularly refers to Jaish al-Islam and other armed opponents as ‘terrorists groups’ with whom it will not negotiate.
Staunch regime ally Moscow has stood by the government's demand, saying the opposition delegation should be broadened to include other groups, like Syria's Kurds.
The talks had originally been due to begin on Monday but officials have said they expect a delay of a few days.
On the Turkish-Syrian border, Turkish authorities have detained 23 suspected militants with the Islamic State group who were trying to cross over illegally from Syria.
In a statement published Sunday, the army said 21 children were with the jihadists and were also being held.
