The embargo is used most often as a political weapon. A foreign-exchange control is a restriction on the amount of a particular foreign currency that can be purchased or sold. This has the effect of limiting imports from the country whose foreign exchange is being controlled. Currency devaluation is the reduction of the value of a nation's currency relative to the currencies of other countries. Devaluation increases the cost of foreign goods, while it decreases the cost of domestic goods to foreign firms.
Cultural barriers impede acceptance of products in foreign countries.
Bureaucratic red tape can be one of the most frustrating trade barriers of all. Reasons for Trade Restrictions. Various reasons are advanced for trade restrictions either on the import of specific products or on trade with particular countries. The U.S. Department of Defense is supplied with arms and other weapons through contracts with private businesses. There are some prohibitions restricting arms sales to foreign nations.