What role does the European integration process play in shaping transatlantic relations, if any? The question brings forth the related issue of whether the EU is able to exercise leadership in fostering changes in the international system and through its relationship with the US. The article provides a literature review on the EU as a foreign policy actor, specifically the extent to which it contributed to changes in the international system along a multipolar pattern. To do so, it looks at the EU’s ability to strengthen multilateralism in international trade and its role in international security. The article’s analysis of the EU and its ability to speak with one unified voice is significant in understanding the EU’s role in Transatlantic relations and its ability to become player on its own right with regard to the US in international politics.