Ankara and Moscow have agreed on the early delivery of Russian S-400 air defense systems to Turkey, the leaders of the two countries said on Tuesday.

Axar.az reports quoting Anadolu agency.

Speaking at a joint news conference at the Presidential Palace in Ankara, Turkish President Recep Tayyip Erdogan and his Russian counterpart Vladimir Putin said they have agreed to shorten the duration of the systems’ delivery, without giving further details.

The S-400 is Russia's most advanced long-range anti-aircraft missile system with a capacity of carrying three types of missiles capable of destroying targets including ballistic and cruise missiles.

The system can track and engage up to 300 targets at a time and has an altitude ceiling of 27 kilometers (17 miles).

The Turkish president said that the production of the missile systems continued.

Erdogan also said the number of Russian tourists visiting Turkey has reached 4.7 million people and is expected to reach 6 million next year.

"Our trade volume [with Russia] has surpassed $22 billion dollars with a 32 percent increase, according to our calculations compared to the previous year," he said, referring to years 2016 and 2017.

“Our goal is to reach $100 billion,” Erdogan added.

Putin said Russia is constructing two undersea pipelines and will build an additional ground gas pipeline as part of TurkStream pipeline project.

The TurkStream project is a direct pipeline from Russia to Turkey with 15.75 billion cubic meters of gas capacity set aside for Turkey's use while a second line with the same 15.75 billion cubic meter capacity is planned for Europe's needs.