European Commission President Jean Claude Juncker warned Greeks that a “No” vote on Sunday’s referendum will “dramatically weaken” Greece’s position, Reuters reported on Friday. Juncker did not answer questions on whether a “No” answer would automatically mean the end of negotiations between the Greek side and the institutions. “The program has come to an end, there are no negotiations under way. If the Greeks vote ‘No,’ they have done everything but strengthening the Greek negotiation position,” Juncker said. Previously during the week, Juncker said he felt “betrayed” by the Greek government and had urged Greeks to vote “Yes” in the referendum. Today he said that even a “Yes” would bring “tough negotiations” for Greece.