EDITORIAL USE ONLY - NO COMMERCIAL OR BOOK SALES. A Greek flag flutters by the hand of a statue of former British Prime Minister William Ewart Gladstone in Athens June 17, 2015. The Greek central bank warned on Wednesday that the country would be put on a "painful course" towards default and exiting the euro zone if the government and its international creditors failed to reach an agreement on an aid-for-reforms deal. REUTERS/Yannis Behrakis