UNTERM :
Mail and Pouch Unit = Groupe du courrier et de la valise diplomatique
Diplomatic Pouch Service = Groupe de la valise diplomatique


Yes, such a thing exists. Here's a picture of one: http://www.versapak.co.uk/images/Diplomaticbag.gif. Americans call it the diplomatic pouch, the British call it the diplomatic bag, and the French call it la valise diplomatique. I'll call it the diplomatic bag for brevity and because that's what the current treaty calls it. But the diplomatic bag is more of a concept than a specific physical object. It's a means by which governments and their ambassadors can send items to one another without fear that the goods will be detained or inspected by foreign governments.
http://www.straightdope.com/columns/read/2234/is-there-such-...