Greece and its international creditors are tempting fate by repeatedly testing deadlines over deals to extend the Greek bailout program, U.S. Treasury Secretary Jack Lew said in an interview to Yahoo Finance editor-in-chief Andy Serwer on Friday. “The risk of an accident goes up the more times you have these [situations, and] everyone rushes to a deadline,” said Lew, who has been in regular touch with European leaders including Greek Prime Minister Alexis Tsipras. “I hope they can reach an agreement that prevents Greece from going through the deep pain that a breakdown would cause, and it doesn’t create risks to either the European or the global economy. This is not the time for a shock,” he added one day before the crucial Eurogroup. According to Lew, Greece has to move with some very painful adjustments, difficult fiscal policies and reforms, while its creditors should show flexibility. He also underlined the need of a conversation about some kind of restructuring of the Greek debt.