Millions of Greeks are voting in a crucial referendum on whether to accept the terms of an international bailout.
The government has urged a “No” vote, but the “Yes” side warns this could see Greece ejected from the eurozone.
“No one can ignore the will of a people,” Prime Minister Alexis Tsipras said, after voting. First results are expected on Sunday evening.
Greeks appear evenly divided over the issue, according to opinion polls. Turnout is expected to be high.
The governing radical-left Syriza party has criticised the bailout terms as humiliating. Its leading figures say rejecting the terms could give them more leverage in talks over the country’s massive debt.
However, international creditors have warned that a “No” vote could choke off vital funding for Greek banks and lead to “Grexit” – a chaotic departure from the common European currency.
The “Yes” campaign has framed the vote in just such terms – as a referendum on Greek membership of the eurozone.
Banks have been shut and capital controls in place since the start of the week, after the European Central Bank declined to give Greece more emergency funding.
The country’s current bailout then expired on Tuesday and Greece missed a €1.6bn (£1.1bn) payment to the International Monetary Fund (IMF).
Casting his ballot, Finance Minister Yanis Varoufakis described the referendum as “a holy moment” that “gives hope that the common currency and democracy can co-exist”.
At the scene: The BBC’s Mark Lowen in Athens
Under a cloudless sky they are streaming into this Athens polling station on a day that will shape the fate of Greece and of Europe. It is the climax of the Greek debt story: when this nation will accept or reject the entire eurozone strategy of the past five years.
If Greeks say “Yes”, it would be hard to see this government staying put, having led the campaign against the measures. If it is a “No”, emergency funds to Greek banks would be in jeopardy and eurozone leaders say a euro exit would be hastened. That’s simply scaremongering, says the Greek government. But if negotiations do resume, there will be plenty of bad blood.
This campaign has profoundly divided Greeks. Tassos, voting “Yes”, told me that Greece belongs in Europe. On the other side, 83-year-old Anastasia told me she couldn’t survive on her meagre pension and was voting “for my homeland”.
What is the referendum about?
Mr Varoufakis earlier told local media that the EU had “no legal grounds” to throw Greece out of the euro.
The finance minister said banks would reopen on Tuesday, whatever the outcome, and that Prime Minister Alexis Tsipras would still reach an agreement with creditors if the result was “No” in the referendum.
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Media captionRos Atkins takes a look at the numbers behind Greece’s referendum
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Media captionKey figures in Greek politics have already cast their ballots
French Economy Minister Emmanuel Macron said negotiations should continue even in the case of a win for the “No” vote, and that Europe could not “crush an entire people”.
Meanwhile, German Finance Minister Wolfgang Schaeuble, one of Greece’s harshest critics, suggested that if Greece were to leave the eurozone, it might only be temporary.
Greece was a member of the eurozone, “whether with the euro or temporarily without it – only the Greeks can answer this question,” he told the German newspaper Bild on Saturday. “And it is clear that we will not leave the people in the lurch.”
Ballot paper question
“Must the agreement plan submitted by the European Commission, the European Central Bank and the International Monetary Fund to the Eurogroup of 25 June, 2015, and comprised of two parts which make up their joint proposal, be accepted? The first document is titled “reforms for the completion of the current programme and beyond” and the second “Preliminary debt sustainability analysis”.
Voters must check one of two boxes – “not approved/no” or, below it, “approved/yes”
Voices from a Greek island
The question that makes (almost) no sense
Capital controls have been in place in Greece over the past week
Electoral workers have raced to get polling stations ready in time, with army helicopters being used instead of boats to rush ballot papers to the islands. Nearly 10 million people are eligible to vote.
Several European officials have complained in strong terms about Greece’s abrupt decision to hold a referendum on the terms of a bailout offer they say is no longer on the table.
Greece’s Syriza-led government was elected in January on an anti-austerity platform.
The European Commission – one of the “troika” of creditors along with the International Monetary Fund and the European Central Bank – wants Athens to raise taxes and slash welfare spending to meet its debt obligations.
Lenders’ proposals: Key sticking points
VAT (sales tax): Alexis Tsipras accepts a new three-tier system, but wants to keep 30% discount on the Greek islands’ VAT rates. Lenders want the islands’ discounts scrapped
Pensions: Ekas top-up grant for some 200,000 poorer pensioners will be phased out by 2020 – as demanded by lenders. But Mr Tsipras says no to immediate Ekas cut for the wealthiest 20% of Ekas recipients
Defence: Mr Tsipras says reduce ceiling for military spending by €200m in 2016 and €400m in 2017. Lenders call for €400m reduction – no mention of €200m