As you may be aware Apple is looking at using custom built in SIM cards for their future iPhone, and apparently this move isn’t going down too well with iPhone carriers over in Europe as the word is some have warned Apple that if they go ahead the carriers will take action.

According to an article over on TiPb by George Lim and by way of the Financial Times, European carriers have warned Apple that if the iPhone company goes ahead with a custom built-in SIM the carriers might pull their subsidy of the iPhone.

Some of the European carriers known to have concerns over the custom iPhone SIM include Vodafone UK, Spain Telefonica and Orange France, and apparently estimations state that if the iPhone loses subsidy global sales would fall roughly 12 percent.

Stanford C. Bernstein analyst Robin Bienenstock has said, “Any decision by Apple to introduce an iPhone with a Sim embedded would undermine the operators’ relationship with their customer and such a move could ultimately prove to be the first step in a process in which the mobile operators cede customer control to handset vendors like Apple.”

Now obviously Apple and the carriers have declined to comment, but without carrier subsidy the iPhone would cost approximately $600, so the question is, if carriers refused to subsidise an iPhone with a custom built-in SIM would people still buy it or would it just become too expensive?