Venezuela's President Nicolas Maduro (C) attends a private meeting with Nanda Kishor Pun (3rd L), Vice President of Nepal, next to Venezuela's Oil Minister and President of the Venezuelan state oil company PDVSA Eulogio del Pino (R) and Venezuela's Foreign Minister Delcy Rodriguez (2nd R), during the 17th Non-Aligned Summit in Porlamar, Venezuela September 18, 2016. Miraflores Palace/Handout via REUTERS

Venezuela's President Nicolas Maduro (R) welcomes Iranian President Hassan Rouhani to the 17th Non-Aligned Summit in Porlamar, Venezuela September 17, 2016. REUTERS/Marco Bello

A sale sign is seen outside a souvenir shop in London, Britain September 18, 2016. REUTERS/Stefan Wermuth

Venezuela's President Nicolas Maduro talks to the media during a news conference after the 17th Non-Aligned Summit in Porlamar, Venezuela September 18, 2016. REUTERS/Marco Bello

A sightseeing bus drives past the Houses of Parliament in London, Britain September 18, 2016. REUTERS/Stefan Wermuth

Venezuela's President Nicolas Maduro talks to the media during a news conference after the 17th Non-Aligned Summit in Porlamar, Venezuela September 18, 2016. REUTERS/Marco Bello

Venezuela's President Nicolas Maduro shakes hands with Iranian President Hassan Rouhani (L) as they arrive for a family photo during the 17th Non-Aligned Summit in Porlamar, Venezuela September 17, 2016. REUTERS/Marco Bello

Swiss President Johann Schneider-Ammann and European Commission President Jean-Claude Juncker attend a news conference in Zurich, Switzerland September 19, 2016. REUTERS/Ruben Sprich