BRUSSELS, May 5 -- Foreign policy chief of the European Union (EU) Catherine Ashton announced on Monday that David O'Sullivan was appointed as the head of the EU delegation to the United States, according to the European Commission's website.

O'Sullivan has been the chief operating officer of the European External Actions Service since its creation. Prior to that, he held a number of senior positions in the European Commission, including that of secretary general and director-general for trade.