Spanish air defence systems were deployed to Incirlik military base in the southern Turkish province of Adana in 2015 as part of a NATO operation, El Pais newspaper said.
There are 150 Spanish soldiers at the base. The current agreement expires in December, but the possibility of an extension for another six months was also considered, according to diplomatic sources. The Spanish government needs to decide soon whether to extend the agreement or not.
In case of aggravation of the conflict in Syria, Madrid would raise the issue of withdrawing air defence systems at NATO, the newspaper said.
On Wednesday, Turkey started Operation Peace Spring against Kurdish fighters as well as the Daesh terrorist group to neutralize alleged terror threats against Turkey and establish a safe zone.
The Turkish offensive in northern Syria has been condemned as aggression by Damascus. Russia has called on Turkey to assess the situation in order not to hamper earlier efforts to settle the Syrian crisis.
The operation has also been met with criticism from regional countries and blocs, including the Arab League, and Western states, including European Union members.
*Daesh (ISIS, ISIL, IS, Islamic State) is a terrorist group banned in Russia and many other states.