If Sasuke tries something funny, I think both will, naruto said the next time they fight they will both die and we know how naruto doesn't like to go back on his word.
Unless naruto just means that he's just going to kill Sasuke and a piece of him will die and since he killed his best friend he gets ms, end if story
BTW: I'm just kidding about the end
In all honesty, I want sakura to die so naruto will go all ape sh!t.I like it when he loses control