calling switzerland
Switzerland is a European country which has been neutral in many historical conflicts, including the two world wars. When someone "calls Switzerland", they are claiming to be neutral in an argument.
#1: Stacey got mad at her boyfriend because instead of taking her side in a fight with her room mate, he called 'switzerland' and left the room.
#2: guy 1: Dude, who's right, me or Bill?
guy 2: I'm not getting involved. I'm calling switzerland.
#2: guy 1: Dude, who's right, me or Bill?
guy 2: I'm not getting involved. I'm calling switzerland.