In this June 15, 2012, file photo, Russian President Vladimir Putin, left, and ExxonMobil CEO Rex Tillerson shake hands at a signing ceremony of an agreement between state-controlled Russian oil company Rosneft and ExxonMobil at the Black Sea port of Tuapse, southern Russia. (Mikhail Klimentyev/RIA-Novosti, Presidential Press Service via AP, Pool, File)