Turkey has given the Syrian government until the end of this month to withdraw from recently seized territory in Idlib province, where several Turkish observation stations are besieged, or face military action.

“I expressed the need for the regime forces to fall back to Sochi deal borders in my phone call to Russian President Vladimir Putin last night,” Erdogan said in an address to his party’s group meeting on Wednesday.

“We hope that they will complete retreating behind our stations in February. If they don’t, we will be forced to [do] it ourselves.”

Erdogan's remarks came after Syrian government forces shelling killed eight Turkish soldiers on Sunday near the strategic town of Saraqeb, where Turkey has been deploying tanks, armoured vehicles, rocket launchers and commandos to stop the offensive.

The town sits on the M4 and M5 highways, and taking it would expose Idlib city, the opposition's last major stronghold, which would be in artillery range.

Forces loyal to President Bashar al-Assad, backed by the Russian military, have made rapid gains in recent weeks, as they look to prise northwestern Idlib province from rebel hands.

The UN estimates more than 500,000 people have been displaced towards the Turkish border since fighting intensified in December.

On Monday, the Turkish military retaliated for the deadly shelling by pummelling Syrian government positions. Ankara claimed it had "neutralised" more than 70 Syrian soldiers, based on radio communications it had intercepted.

A turning point

Erdogan said on Wednesday that the deadly attack on Turkish forces was a turning point for Ankara in Syria.

“As the regime responds to the smallest [ceasefire] violations with heavy attacks that also target civilians, from now on we will retaliate to the regime violations in the same way,” Erdogan said.

“Any air or ground attack on our military or elements aligned with us, regardless of the identity of the source and without warning, will be reprised.”

Turkish air and ground units will freely operate in all of Idlib and conduct operations if needed, he added.

Despite Erdogan’s warnings, local reports indicated that Assad's forces on Wednesday continued to seize more territory to the east of Saraqeb.

'Assad's forces will be on the Turkish border before the end of February. They should act now' - Former Turkish official

One former Turkish official who follows the situation on the ground was pessimistic.

“I really don’t understand the February deadline," he told Middle East Eye.

“They are closing in on Idlib city. They don’t attack Turkish positions but rather move around them and still make progress towards the north, to the border. Assad's forces will be on the Turkish border before the end of February. They should act now.”

Others believe Turkey gave more than 20 days to Damascus to open up space for negotiations with Russia.

"It has to do with Turkish military logistics and deployment. Ankara will reinforce the region," Omer Ozkizilcik, an expert on Syrian affairs at Ankara-based think-tank SETA, told MEE. "There should be a certain line, if crossed, that Turkey will be forced to stop directly."

A Turkish official told MEE that Turkish troops were standing their ground and targeting Assad's forces with howitzers and mortar fire.

“If the order comes, they can easily sweep the area south of Saraqeb and push Assad's forces back,” the official said.

Wary of Russia

Erdogan was also careful in his speech in his criticism of Russia. He said that Ankara knows Damascus would be unable to advance without Russian air support and Iranian backing on the ground.

“We have no intention or desire to confront our allies or other countries. We will never forget the ones who show us friendship or animosity on this path to reach an appropriate solution for both the people of Turkey and Syria until stability returns,” Erdogan said. “We give special attention to our friendship with Russia.”

Turkey's relations with Russia have been tense since last week, when Erdogan declared that Moscow wasn't abiding by the de-escalation agreements it had promised to uphold in Idlib.

Since the clashes between Turkish and Syrian forces earlier this week, Russian state media have published a series of anti-Turkey reports, the kind not seen since relations between Ankara and Moscow hit a nadir in 2016.

Russian state news agencies Rossiya Segodnya and TASS claimed in separate articles on Tuesday that Turkey had played a role in the creation of the Nusra Front, al-Qaeda's former Syrian arm.