Russia and Turkey have agreed to work to "normalize" the situation in the contested northern Syrian province of Idlib. "We understood what we need to do together to solve this problem," said Russian President Vladimir Putin at a meeting with Turkish President Recep Tayyip Erdoğan in Moscow. "Additional joint steps" had been agreed to de-escalate the situation. Erdoğan also called the meeting "meaningful".

A concrete plan to end the crisis in the last major rebel stronghold in Syria, however, did not present the two presidents.

Turkey supports the rebels in the Syrian civil war, Russia is the protector of the Syrian government. Erdoğan and Putin had agreed a ceasefire between rebels and government forces in Idlib last September in Sochi, Russia. The agreement averted an impending offensive by power-holder Bashar al-Assad, but the agreement was never fully implemented. Since the end of April, the Assad troops, with the support of the Russian Air Force, are again increasingly attacking the predominantly Islamist rebels. Just recently, Syrian troops advanced to areas where Turkey has observation posts.

Last week a Turkish military convoy in Idlib was attacked by Syrian and Russian military jets. According to a statement by the Ministry of Defense in Ankara, three civilians were killed and twelve others injured in the bombing. "The situation has become so complicated that our troops are in danger right now," Erdoğan said. The "provocations of the Syrian regime" reached a point where they risked the lives of Turkish soldiers in the region. However, Turkey would "take all necessary measures" to protect its soldiers, the head of state warned.

On September 16, Erdoğan and Putin want to meet Iranian President Hassan Ruhani for another Syria summit in Ankara.

The business relations continue

In Turkey, meanwhile, other components of the Russian missile defense system S-400 arrived on Tuesday. This was confirmed by the Turkish Ministry of Defense. These are the first deliveries for the second battery. Until all parts are there, it should take about a month. The first battery arrived in Ankara on several airline flights from Russia in mid-July. That had triggered tensions with the US. The US government considers the use of Russian military technology in NATO airspace as a danger - especially for the new US stealth fighter jet F-35.

Turkey was to receive even F-35 jets and was also involved in their construction. After the first deliveries, the US suspended Turkey from the F-35 program. Other sanctions threatened by the US Congress and the Pentagon, however, did not materialize for the time being.

The S-400 is a mobile air defense system that can shoot planes, missiles and other objects from the sky. The units, which usually consist of several missiles, a radar and a command post, can be transported by truck. The S-400 can work with short-, medium- and long-range rockets.