Oscar Niemeyer was part of the multinational team of leading architects who projected the headquarters of the United Nations in New York City:


"Rather than announce a competition for the design of the facilities for the headquarters, the UN decided to commission a collaborative effort among a multinational team of leading architects. The American architect Wallace K. Harrison was named as chief architect and director of planning, and a board of design consultants was nominated by member governments. The board consisted of N. D. Bassov of the Soviet Union, Gaston Brunfaut (Belgium), Ernest Cormier (Canada), Le Corbusier (France), Liang Seu-cheng (China), Sven Markelius (Sweden), Oscar Niemeyer (Brazil), Howard Robertson (United Kingdom), G. A. Soilleux (Australia), and Julio Vilamajó (Uruguay).[8]"


source: [link to en.wikipedia.org]