According to the report,
Samsung Electronics recently asked Apple for a significant price raise in (the mobile processor known as) application processor. Apple first disapproved it, but finding no replacement supplier, it accepted the (increase.)The A-series of processors (such as the A6X, in Apple's fourth-generation iPad) are custom-designed by Apple. However, they are built for Apple by Samsung.
It's something that has become more and more uncomfortable as the relationship between the two companies has deteriorated, what with Samsung's dominance not just in Android smartphones but in smartphones, period.
A recent Strategy Analytics report said that Samsung's Galaxy S III smartphone overtook the iPhone 4S in calendar year Q3 2012, something that would have been unheard of not that long ago.
Recognizing this, Apple has been trying to minimize its relationship with Samsung. That said, until and unless Apple can come up with an alternate supplier for its processors, it's stuck with Samsung.