ANKARA, Jan. 24 (Xinhua) -- Intense battles continued Tuesday between Turkish forces and the Kurdish-led troops on the outskirts of the Kurdish-controlled Afrin enclave in northern Syria.
On Tuesday, Russian President Vladimir Putin and Turkish President Recep Tayyip Erdogan had a phone conversation about the current situation in Afrin, Kremlin's press service said.
"The sides stressed the importance of continuing active joint work to resolve the crisis, which should be based on the principles of preserving territorial integrity and respect for the sovereignty of Syria," Russia's Sputnik News Agency quoted a Kremlin statement as saying.
Putin and Erdogan also discussed preparations for the Syrian National Dialogue Congress to be held in Sochi, Russia on Jan. 29-30, expressing the hope that the congress will pave the way for a long-term political settlement in Syria.
So far, 22 civilian deaths have been reported by the monitor group Syrian Observatory for Human Rights since the Turkish side on Saturday launched the cross-border military campaign, dubbed as "Operation Olive Branch."
Turkey aimed to unleash an offensive along with the Ankara-backed Syrian rebels against the Kurdish People's Protection Units (YPG) and the Kurdish-led Syrian Democratic Forces in Afrin.
The YPG was deemed by Turkey as a terror group affiliated to the outlawed Kurdistan Workers' Party based in the country and Iraq.
With the military operation going into the fourth day, at least 260 members of the YPG have been killed, the Turkish army said, while the death toll of the Turkish army rose to three.
Turkey's presidential spokesman Ibrahim Kalin said Tuesday in a statement that the operations in Syria will continue "until all terrorists are fully eliminated" and 3.5 million Syrian refugees return home.
Turkey currently hosts around 3.5 million Syrians who have fled violence in Syria since the civil war broke out in early 2011.
Ankara's military operation came after the United States released statements on a planned Kurdish-led Border Security Force (BSF) to be established in Syria along the 900-km border with Turkey.
The BSF would be mainly constituted by the YPG, which was supported politically and militarily by the United States since 2014 in the battle against the Islamic State (IS) in Syria.
The plan to build the BSF angered Ankara, with Erdogan declaring that he would "kill the force before it is even born."
On Monday, U.S. Defense Secretary James Mattis said "we are very alert" to the situation in Afrin.
"Turkey has legitimate security concerns," Mattis told reporters, adding that the United States and Turkey were "working now on the way ahead" through diplomatic and military channels.
On the same day, a Turkish official rejected Russian media reports that said the Turkish military operation along the Syrian border will be limited to Afrin.
The attitude coincided with that of Turkish Foreign Minister Mevlut Cavusoglu, who said in Vancouver, Canada last week that "Turkey's measures against the YPG cannot be limited to Afrin alone. There is also Manbij and east of the Euphrates River."
The operation launched by Turkish military and allied Free Syrian Army opened a new front in Syria's seven-year-old war.
It is Turkey's second major incursion into Syria after the August 2016 Euphrates Shield Operation in an area to the east of Afrin against both the YPG and IS militants.