The message for anyone trying the cashpoint at the National Bank of Greece in downtown Athens was curt and to the point. "This ATM is unavailable for withdrawals," it read. "Sorry for any inconvenience."
Its empty vault, however, was not due to the brisk weekend trade in the nearby tourist cafes, but to the large numbers of locals withdrawing cash while they still could. And with fears now rife that Greece's banks could collapse in coming days, "inconvenience" was perhaps an understatement.
That, though, was the grim prospect facing Greece on Sunday, after finance chiefs running its €240bn bail-out program ruled that they too were "unavailable for withdrawals. Bereft now of any means to pay a $1.5bn debt instalment to its other big creditor, the IMF, on Tuesday, Athens is finally in breach of its overdraft on an epic scale.
"I heard that the banks were going to shut this week so I came to take out some money," said Evi Costas, 40, just after her bank card was swallowed by a Eurobank ATM just off Syntagma Square. "I wanted to withdraw €500, but what will I do now"
Her card having vanished, Ms Costas was planning to return the bank on Monday morning to seek its return. But therein lay further uncertainty. As of Sunday night, noone was quite sure when the banks would be opening again, be it on Monday or indeed any day next week.
With nearly half a billion euros removed from the banks between Saturday night and Sunday morning alone, the government has been forced to bow to pressure and enforce at least a week long bank holiday effective from Monday.
With nearly half a billion euros removed from the banks between Saturday night and Sunday morning alone, the government is under mounting pressure to keep the banks shut to stop them being emptied completely.
Yet even that basic measure is now a point of contention between Greece's Left-wing government and its bank managers in Brussels. While the European Central Bank has strongly advised it, Yanis Varoufakis, Greece's firebrand finance minister, said on Sunday that it mean admitting that Greece's Eurozone days were over.
Hence the continuation on Sunday of the long lines of people outside the few ATMs that still had cash in them. True, many of those queuing were simply anxious about having cash in hand for the next few days, rather than trying to remove their entire life savings and stash them at home.
But with confidence in Greek financial institutions at an historic low, the "Bank Under the Bed" is about the only one doing well at the moment. Since Mr Tsipras's government was elected on its radical, anti-austerity ticket back in January, anxious Greeks have withdrawn an estimated €30bn in savings accounts, adding to the general sense of a 1930s-style meltdown.
"If we default and go back to using the drachma it will be like going back to the wartime era," added Ms Costas. "Only this time round, the drachma will be like some useless Third World currency with no value."
The fear that Greece might eventually bow out of the Euro has been around in Athens for months now, but on Saturday night, what had once just seemed like a worst-case scenario suddenly loomed as the most likely outcome.
That was when Mr Tsipras, having argued to the wire with Eurozone leaders over the terms of the continued bail-out program - which is also due to expire on Tuesday - suddenly announced that he would put the matter to a national referendum this coming Sunday.
For a country that was the birthplace of democracy, that might sound like a reasonable plan. It did not go down well, though, with Eurozone's finance chiefs, who saw it as yet more brinkmanship by Mr Tsipras in his bid to make them blink first.
Yet in playing this latest hand of Greek financial poker, Mr Tsipras also seems to have forgotten that the bank always has the upper hand. For in postponing the decision on the bail-out program until next Sunday, he gambled that Brussels would extend the deal itself for a week, allowing it to make its the €1.5bn payment due to the IMF on Tuesday. It was at that point that the Eurozone's finance ministers shook their heads, saying that as Athens had "unilaterally" ended the talks, there would be no extension, not even for a few days.
While the European Central Bank later said that it would continue to throw Athens a financial lifeline, allowing local banks to continue withdrawing, the only thing both sides now agree on is that nobody really knows what will happen next. The decision of the bookmaker, William Hill, to stop taking bets on a Grexit due to the rapidly shortening odds, seem as informed a prediction as any yesterday.
In the meantime, those waiting at the ATMs pass the time debating how they will vote in Sunday's referendum, not that it offers much of a choice either way. Even those who favour leaving the Eurozone seem to fear that Greece may end up like Afghanistan, or at the very least, neighbouring Albania.
"Europe is a club of cannibals that is trying to strangle Greece," said Lambros Stamoulis, 29, one of the 25 per cent of Greeks currently unemployed. "I will vote 'No' to the bail-out in the referendum. It would be nice to stay in the Euro, but the debt is so huge it would be best to return to the drachma."
"I will vote 'Yes'," said pensioner Costas Papadopolous, 75, after failing to withdraw his monthly pension at the National Bank of Greece ATM in Syntagma Square. "Tsipras has been far too confrontational and he needs to go. In fact, if Europe stops giving us money, that might be a good idea, it might mean we get new elections."
With that he sauntered off, joining two friends who were whiling the hot Sunday afternoon away in a cafe. With the future now so uncertain, that seems about as much of a plan as anyone can make.