Recep Tayyip Erdoğan and Russian President Vladimir Putin praised Thursday a "significant decrease in tensions in the Idlib de-escalation zone" in Syria, the Kremlin said.

The two leaders, who last week agreed on a cease-fire in Syria's northwestern Idlib region, also pledged to continue joint work "to ensure a sustainable ceasefire regime and further stabilization of the situation," the Kremlin said in a statement after the two leaders spoke by phone.

Putin and Erdoğan had a phone call in which it was acknowledged there has been a "significant reduction of tensions in the Idlib de-escalation zone," the Kremlin said.

Turkey launched Operation Spring Shield on Feb. 27 after at least 34 Turkish soldiers were killed last month in an Assad regime airstrike in Idlib province and after repeated violations of previous cease-fires.

The cease-fire deal came amid recent clashes between the Turkish military and Syrian regime forces that left many dead on both sides. As part of the agreement, all military activities will end in Idlib and a security corridor will be established 6 kilometers (3.7 miles) deep to the north and to the south of the M4 highway.

Joint Turkish-Russian patrols will also begin on March 15 along the M4 highway from the settlement of Trumba, 2 kilometers to the west of Saraqib, to the settlement of Ain-al-Havr, according to the deal.

Turkey has long backed some opposition groups fighting against Assad, but its priority now is to stop another influx of refugees.

The Kremlin – which launched an air war in support of Assad in 2015 – sees it as a key success of Putin's foreign policy, with newfound clout and military bases in Syria that establish Moscow as a major player in the Middle East.