BEIRUT Backed by relentless Russian air strikes, Syrian troops and allied militiamen on Wednesday pushed deeper into a major rebel stronghold in the northwestern province of Latakia, a day after seizing a key rebel-held town in the strategic region overlooking the coast, the government and opposition activists said.

The insurgents in the opposition-held area near the Turkish border were collapsing after the town of Salma fell to government loyalists late Tuesday. Salma’s fall marked one of the most significant military victories by the Syrian military since Russia began air strikes in the country last September to shore up President Bashar Al Assad’s forces.

Later Wednesday, the Free Syrian Army and 33 other factions and rebel groups issued a statement saying they would reject scheduled peace talks in Geneva later this month unless humanitarian conditions mentioned in a UN resolution for Syria are fulfilled.

The groups — including the powerful Army of Islam — said that clauses specified in the resolution that call for allowing humanitarian aid to populations in need of it, must first be met.

“We reject going ahead with any negotiations before implementation of humanitarian clauses in UN Security Council resolution 2254 begins,” the statement said.

Syria’s main political group in exile, the Syrian National Coalition, said the statement was not final and did not mean negotiations were completely off.

“I think it’s good for them to use such a statement to put some pressure on the Russian or Iranians to push Al Assad to start implementing confidence building measures,” said SNC vice president Hisham Marwah.

The UN has been urging the belligerents in Syria’s five-year-conflict to the negotiating table on January 25 in an effort to find a resolution to a civil war that has killed more than 250,000 people and displaced half the country’s population. High-level US, Russian, UN and other diplomats are meeting behind closed doors in Geneva to discuss efforts to those talks.

Later, the International Committee of the Red Cross urged all side to end sieges being carried out across the country because of “because of overwhelming humanitarian needs.”

“The appeal comes after access was granted earlier this week to three towns in the country which have been under siege for months. The populations in all three areas were found to be living in appalling conditions,” ICRC said.

Meanwhile, fighting inside Syria on Wednesday saw government troops seizing the villages of Mrouniyah and Marj Kawkah near Salma as they continued their advances in the region, aided by immense Russian firepower.

Salma, part of mountainous chains near the border with Turkey known as Jabal Al Akrad and Jabal Al Turkmen, has been under rebel control for the past three years.

The town, where members of Al Assad’s Alawite minority sect once co-existed with majority Sunni Muslims, overlooks the largely Alawite coast and is about 12km away from the Turkish border. Turkey is a key supporter of insurgents in the area, which is mostly inhabited by Syrian Turkmen, an ethnic minority with close ties to Turkey.

“Whoever controls Salma gains control all those surrounding areas which it overlooks,” said Zakariya Ahmad, an opposition activist in the nearby Idlib province.

He said the town fell after 93 days of fighting and daily barrel bombs and air strikes. He said activists in the region had reported 92 air strikes believed to be Russian on Salma in the last 24 hours before it was fully seized by government troops.

“It was hell on earth,” he said.

Salma’s recapture further improves Al Assad’s position ahead of the planned peace talks, the latest in a string of military achievements by the government recently, supported by Russian air power and Lebanon’s Shiite militant Hezbollah group.

Fawaz Gerges, a Middle East expert at the London School of Economics, said Russia was trying to send a powerful message to Turkey following the downing of their plane in November in the area, showing that they can exact revenge.

“Salma is really a major breakthrough, not just for the Syrian army, for Russia as well,” he said, adding that losing the town was a significant loss for the opposition.

“The rebels thought they could turn it into a spearhead to deal a mortal blow against the regime” into its Alawite heartland, he added.

Russia began conducting air strikes in Syria on September 30 against Daesh and “other terrorists,” but much of the Russian air strikes have targeted areas where the Daesh has no presence.

Jabal Al Akrad, where Wednesday’s fighting was focus, is also close to the rebel-held northwestern province of Idlib, which has also been frequently targeted by Russian warplanes since Moscow launched its air campaign. It is controlled by a consortium of mainstream and extremist insurgent groups including the ultraconservative Ahrar Al Sham and the Nusra Front.

Latakia province includes key strongholds of Al Assad and the Alawite religious minority.

Sharif Shehadeh, a Syrian member of parliament, said the capture of Salma “effectively brings the entire coastal area under Syrian army control”.

He said the combination of Syrian ground troops and Russian air cover was proving extremely effective and predicted “big changes” that would change the battlefield by mid-year.