Russian President Vladimir Putin, left, speaks to Turkey’s President Recep Tayyip Erdogan during their meeting in the Kremlin in Moscow, Russia, Friday, March 10, 2017.

President Vladimir Putin hosted his Turkish counterpart, Recep Tayyip Erdogan, on Friday for talks focusing on Syria, where Russia and Turkey have launched mediation efforts and coordinated military action.

The two countries brokered a cease-fire in December that helped reduce the scale of fighting between Syrian President Bashar Assad and the opposition, and they also co-sponsored two rounds of talks this year between Assad’s government and its foes. A third round is set for next week.

“We are actively working to solve the most acute crises, first of all in Syria,” Putin said as he greeted Erdogan at the start of the talks. “I’m very pleased to note, and few seemed to expect it, that our military and special services have established such efficient and close contact.”

Russia and Turkey also coordinated their operations against ISIS in Syria. A Russian air raid last month accidentally killed three Turkish soldiers, but the incident didn’t derail the military coordination.

Earlier this week, the chief military officers from Russia, the United States and Turkey met in the Turkish city of Antalya in an apparent attempt to work out additional steps to prevent incidents and help assuage mutual mistrust between Turkish-backed Syrian opposition forces, US-backed Kurdish forces, and Russian-allied Syrian government forces all fighting their way toward ISIS’s de facto capital, Raqqa.

The increasingly close cooperation on Syria between Russia and Turkey marked a sharp turnaround for the two nations, which have backed opposing sides in Syria, with Moscow siding with Assad and Turkey supporting his foes since the start of the Syrian conflict six years ago.

The conflicting interests led to the downing of a Russian warplane by a Turkish jet at the Syrian border in November 2015, which put the two nations on the verge of a direct military conflict. Moscow responded by barring the sales of package tours to Turkey and halting imports of agricultural products, moves that badly hurt the Turkish economy.

Erdogan’s apologies for downing the plane helped rebuild ties, and Putin offered firm support to the Turkish leader in the wake of a botched coup last July.

Despite the rapprochement, Russia has moved gradually to lift economic restrictions, keeping some in place as an apparent motivator for Turkey. On the eve of the Kremlin talks, it allowed the imports of a few other agricultural products from Turkey.

“We are pleased to see our ties recovering at a quick tempo,” Putin said.

Erdogan noted that cooperation in building a prospective Russian natural gas pipeline and a nuclear power plant in Turkey also have regained pace.