The logo of the Organization of the Petroleum Exporting Countries (OPEC) is pictured at its headquarters in Vienna, Austria, May 30, 2016. REUTERS/Heinz-Peter Bader - RTX2ET3V

A nurse (L) hands out a red ribbon to a woman, to mark World Aids Day, at the entrance of Emilio Ribas Hospital, in Sao Paulo December 1, 2014. REUTERS/Nacho Doce

Supporters of Venezuela's President Nicolas Maduro gather in a street near the Venetur Hotel Convention Center where the 17th Non-Aligned Summit takes place in Porlamar, Venezuela September 16, 2016. REUTERS/Marco Bello

North Korea's Foreign Minister Ri Yong-ho (C) arrives at the Venezuela's late President Hugo Chavez statue unveiling event at the entrance of the Venetur Hotel Convention Center, venue of the 17th Non-Aligned Summit in Porlamar, Venezuela September 16, 2016. REUTERS/Marco Bello

Bolivia's Foreign Minister David Choquehuanca (C) speaks during the Venezuela's late President Hugo Chavez statue unveiling event at the entrance of the Venetur Hotel Convention Center, venue of the 17th Non-Aligned Summit in Porlamar, Venezuela September 16, 2016. REUTERS/Marco Bello

A statue of Venezuela's late President Hugo Chavez is seen at the entrance of the Venetur Hotel Convention Center, venue of the 17th Non-Aligned Summit in Porlamar, Venezuela September 16, 2016. REUTERS/Marco Bello

Venezuela's Foreign Minister Delcy Rodriguez (C) speaks during the Venezuela's late President Hugo Chavez statue unveiling event at the entrance of the Venetur Hotel Convention Center, venue of the 17th Non-Aligned Summit in Porlamar, Venezuela September 16, 2016. REUTERS/Marco Bello

Burundi'sForeign Minister Alain Aime Nyamitwe (C) speaks during the Venezuela's late President Hugo Chavez statue unveiling event at the entrance of the Venetur Hotel Convention Center, venue of the 17th Non-Aligned Summit in Porlamar, Venezuela September 16, 2016. REUTERS/Marco Bello