Why Turkish tanks refuse to attack?

In an exclusive BBC interview, Turkey's prime minister has explained why Turkish ground troops have not been deployed inside Syria to fight Islamic State (IS) militants.

The border city of Kobane has been under attack for over a month by IS members who are being held off by Kurdish fighters.

Now Iraqi Kurdish forces are travelling to Turkey, from where they plan to cross into Syria to battle militants.

http://www.bbc.com/news/world-europe-29804033