ATHENS/BRUSSELS — Greece's ruling Syriza party dismissed reform demands from the country's international creditors as “blackmail” on Thursday as crisis talks to avert a debt default and a euro zone exit entered a critical phase. A parliamentary spokesman for Greek Prime Minister Alexis Tsipras's left-wing party struck a defiant tone a day after euro zone finance ministers accused Athens of refusing to compromise despite a looming deadline to clinch a deal. Tsipras was due to resume talks with Greece's lenders at 9 a.m. (0700 GMT) before the ministers reconvene at 1 p.m. and European leaders begin arriving in Brussels later this afternoon. Without a cash-for-reform deal in the next 48 hours, the chances of Greece averting a default to the International Monetary Fund (IMF) look slim. Failure to repay 1.6 billion euros owed to the IMF on Tuesday could trigger a bank run and capital controls, followed by a slide out of the single currency area. — Reuters