U.S. President Barack Obama shakes hands with Prime Minister Donald Tusk (R) at the Prime Minister's Office in Warsaw June 3, 2014. Obama is visiting Warsaw, Brussels, Paris and Normandy this week ... more 
U.S. President Barack Obama shakes hands with Prime Minister Donald Tusk (R) at the Prime Minister's Office in Warsaw June 3, 2014. Obama is visiting Warsaw, Brussels, Paris and Normandy this week where he is expected to elaborate on the U.S. commitment to counter Russian moves against Ukraine and reassure nervous allies the United States has their backs. REUTERS/Slawomir Kaminski/Agencja Gazeta (POLAND - Tags: POLITICS) THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT IS DISTRIBUTED, EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. POLAND OUT. NO COMMERCIAL OR EDITORIAL SALES IN POLAND. less 
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Reuters | Photo By AGENCJA GAZETA / REUTERS
Tue, Jun 3, 2014 8:12 AM EDT