Erdogan is scapegoat . He is engulf in multiple dire situations, after touching Syria. If he knows, Kurds will be biggest gainer in this whole scenario, he wouldn't touch Syria. Plus, if he enter Syria then he has to confront Kurds and EU and US won't tolerate any type of Kurds confrontation. So, basically Turkey in hard and rock situation ..
But, Saudi are pushing hard, and recently Turk PM came Pakistan for back support. Because, only Pakistan army who is battle hardened army , who been fighting terrorism since last many years. Plus, Syria and Fata terrain is kinda similar, but soldiers are different and battle tactics are totally different. Fight in mountain and fight in concrete rubble is totally different.
Closer defense and trade ties.