President Barack Obama embarks Monday for a trip to Europe, with stops in Poland, Belgium and France.
The U.S. leader's trip comes as Ukraine's government battles pro-Russian separatists. Obama will meet with Ukrainian president-elect Petro Poroshenko in Poland.
The president also meets Wednesday and Thursday with U.S. allies in Brussels at a meeting quickly arranged after leaders decided to boycott a Group of Eight meeting that Russia is scheduled to host this week in Sochi. The boycott is in response to Russia's annexation of Crimea in March.
In France, Obama will speak Friday at Omaha Beach in Normandy for a ceremony marking the 70th anniversary of the allied D-Day invasion against Nazi forces in World War II.
Russian President Vladimir Putin also will attend. No meetings are scheduled between the Russian and American presidents, but British Prime Minister David Cameron is to meet with Putin in Normandy.