Greece's positions in negotiations for a cash-for-reforms deal remain firm and talks with its international creditors will resume at 0900 Brussels time (0700 GMT) on Thursday, a Greek government official said after late-night discussions ended. Negotiations to avert a Greek debt default had stumbled on Wednesday and euro zone finance ministers accused Athens of refusing to compromise despite a deadline next week that could put it on a path out of the euro zone. "The Greek government remains firm on its positions," the official said.