Final answer:
The World Trade Organization (WTO) is the UN agency that promotes international trade among nations. It originated from the GATT agreement and officially began operations in 1995, carrying forward the mission of supervising and liberalizing global trade.
Step-by-step explanation:
The UN agency that promotes international trade among nations is the World Trade Organization (WTO). The WTO came into existence in 1995 as a successor to the General Agreement on Tariffs and Trade (GATT). It plays a pivotal role in facilitating and regulating global trade by providing a forum for countries to negotiate trade agreements and settle trade disputes. Originating from a long lineage of the push for economic cooperation after World War II, the WTO also ensures that trade flows as smoothly, predictably, and freely as possible.
During the Bretton Woods Conference, the International Trade Organization (ITO) was proposed to manage international trade but was never actualized because the United Nations could not reach an agreement on it. Instead, the General Agreement on Tariffs and Trade (GATT) was signed in 1947, serving a similar purpose until it transformed into the WTO in 1995.