Greek banks have been ordered shut and capital controls imposed, Prime Minister Alexis Tsipras announced, pleading for calm after anxious citizens emptied cash machines in a dramatic escalation of the country’s debt crisis. Speaking on national television on Sunday evening, Tsipras said the Bank of Greece had recommended a “bank holiday and restriction of bank withdrawals” from today after the European Central Bank said it would not increase its financial support to Greek lenders, despite early signs of a chaotic bank run. The drastic measures announced by Tsipras topped off a weekend of high drama that began with the leftist premier’s unexpected call for a July 5 referendum on creditors’ latest reform proposals after bailout talks in Brussels collapsed. In response, angry EU and IMF creditors rejected a request to extend the nation’s bailout beyond its June 30 expiry date, sparking fears Greece could default on a key debt payment to the IMF due the same day and possibly crash out of the eurozone. Uncertainty over how events will unfold in coming days prompted long queues of up to a hundred people to form outside some ATMs in Greece. Keen to stave off panic, Tsipras assured Greeks their deposits were “totally safe”. “Any difficulties that may arise must be dealt with calmness. The more calm we are, the sooner we will get over this situation,” he said, adding that Athens had again requested a “prolongation of the (bailout) programme”. The euro fell sharply against the dollar and safe-haven US government debt futures rallied as investors exhibited fears of a Greek default and exit from the euro zone. "That is going to have a real big impact on markets and that will generate increased volatility," said Ian Stannard, European head of FX strategy at Morgan Stanley in London. The euro fell nearly 2 US cents to a one-month low in early Asia Pacific trade. The fear of contagion produced a sharp move into safe-haven government debt. US 10-year Treasury futures rose 1 27/32 in active trading early. The bank holiday announced by Tsipras is expected to last at least until Monday, July 6, the day after the planned referendum. The Athens stock exchange will be closed as the government tries to manage the financial fallout. It remains unclear how long capital controls will remain in force. In Cyprus, which imposed similar measures in 2013, they were not fully lifted until April of this year. Watch: Greece announces bank holiday Tsipras faces growing political pressure with opinion polls suggesting a majority of Greeks could turn their back on his call to reject the bailout and instead decide to support the lenders’ package in next Sunday’s referendum. If they do, he would face pressure to resign, leaving the way open for new elections. Former conservative Prime Minister Antonis Samaras, who on Sunday met Greek head of state President Prokopis Pavlopoulos, said Tsipras should drop the referendum plans and return to the negotiations or make way for a government of national unity. Greeks have pulled billions of euros out of their accounts. Long queues formed in supermarkets on Saturday as shoppers stocked up on essentials. Greek Finance Minister Yanis Varoufakis meanwhile said there was still time for a compromise, urging creditors to show some “goodwill” and come up with an improved proposal ahead of the plebiscite. “We remain open to new proposals by the (creditor) institutions,” he told the German daily Bild . In Athens, school teacher Yiannis Grivas said he had withdrawn his entire 940-euro salary on Friday so “I have enough to live on for a few weeks.” He added: “I am not afraid of capital controls, I never take out more than 50 euros a day anyway.” In the capital’s upscale Kolonaki area, 32-year-old Anna tried in vain to find a working cash machine. “There is no more money,” she said, adding that she hoped her countrymen would vote in the referendum “to stay in the eurozone and the European Union” and that “the nightmare will finally end”. Since Friday night alone, 1.3 billion euros (US$1.45 billion) have been withdrawn from the Greek banking system, according to the head of the bank workers’ union Stavros Koukos. A banking source in Greece said only 40 percent of cash machines now had money in them and a host of European governments including London and Paris advised citizens travelling to Greece to carry cash with them. The Frankfurt-based ECB’s governing council earlier Sunday held a crisis telephone conference and pledged to maintain emergency liquidity assistance -- keeping open its life-support for Greek banks and, by extension, the Greek state. But it pledged no extra cash for banks. The move further raised the stakes in Greece’s festering debt crisis after five months of tough bailout talks culminated on Friday night with Tsipras’s shock call for a referendum on creditors’ latest cash-for-reforms offer. French Prime Minister Manuel Valls warned of a “real risk” of Greece leaving the eurozone if it Greeks vote against the EU’s bailout proposals in the planned referendum. But Tsipras, whose Syriza party came to power in January on an anti-austerity platform, has advised voters against backing a deal he said spelled further “humiliation” for a country that has endured five years of recession, turmoil and skyrocketing unemployment. Unless creditors heed Tsipras’s renewed request for a bailout extension, Greece’s rescue plan will formally expire on Tuesday. This will almost certainly mean Greece will default on more than 1.5 billion euros (US$1.7 billion) due to the IMF that same day. Missing the IMF payment does “not spell immediate formal default or even Grexit. But it would put Greece on the slippery slope towards Grexit,” wrote Holger Schmieding, chief economist of Berenberg Bank.