Voters in Greece have overwhelmingly rejected the terms of a new international bailout in a referendum.
With almost all the votes counted, official figures show 61 percent of Greeks rejected the bailout offer.
The astonishingly strong victory by the 'No' camp has overturned opinion polls that had predicted an outcome too close to call.
Greek Prime Minister Alexis Tsipras had campaigned for a "No" vote, saying the bailout terms are humiliating.
Addressing the nation after the referendum, Tsipras says the result shows that democracy cannot be blackmailed.
But he also says Greece is ready to return to the negotiating table.
"Today, considering last week's very difficult circumstances, you made a very brave choice. However I am fully aware that the mandate here is not a mandate to break with Europe, but a mandate to strengthen our negotiation position to seek a viable solution."
The "No" vote means Greece now risks financial and political isolation within the euro zone and a banking collapse if creditors refuse further aid.
But for millions of Greeks the outcome is an angry message to creditors.
"It's a clear answer by the Greek people. We can't take other measures. We can't take any more austerity. At some point, Europe must become a Europe of the people - for the people to be listened to and not only for the technocrats of Brussels and the bankers of the ECB (European Central Bank) to be heard."
"We are Greeks. We won. Justice won. The indignation of the people who have had such a bad time. We're looking to improve the future for our kids."
The Greek government had argued that a "No" vote would be a boost for Greece to secure a better deal from creditors.
Greek officials have immediately said they would try to restart talks with European partners.
However, euro zone officials have shot down any prospect of a quick resumption of talks.
The leaders of Germany and France are calling for a Eurozone summit on Tuesday to discuss the Greek crisis.
Greece and its creditors had been locked in negotiations for months when the government unexpectedly called a referendum on the terms it was being offered.
Banks have been closed and capital controls have been in place since last Monday, after the European Central Bank declined to give Greece more emergency funding.
For more on the story, we are joined by Mike Bastin, director of China Business Center based in London.
