ATHENS, Greece -- Greeks overwhelmingly rejected creditors' demands for more austerity in return for rescue loans in a critical referendum Sunday, backing Prime Minister Alexis Tsipras, who insisted the vote would give him a stronger hand to reach a better deal.

Tsipras gambled the future of his 5-month-old left-wing government on the vote.

The opposition accused him of jeopardizing the country's membership in the 19-nation club that uses the euro and said a "yes" vote was about keeping the common currency. Opposition leader Antonis Samaras announced his resignation after suffering a big defeat in Sunday's referendum.

More from the hours after the initial projection was released (all times local):

10:55 a.m.

French Finance Minister Michel Sapin says it is up to Greece to come up with an offer after the vote, hours before German Chancellor Angela Merkel heads to Paris for an emergency meeting with the French president.

"The basis of a dialogue is on the table, but it's up to Greece to show us that it takes the dialogue seriously and that it knows it can stay in the euro and that there are decisions to make," Sapin told Europe 1 radio Monday. He said the referendum clearly showed strong support for the Greek prime minister, but beyond that its consequences were not immediately clear.

France had no desire to see Greece leave Europe but Sapin insisted that the bloc would not be destabilized if that happened. "It's Greece that is in difficulty. Europe is not in difficulty — Europe is facing a Greek difficulty."

10:15 a.m.

Government spokesman Gabriel Sakellaridis said in a statement that a replacement for Finance Minister Yanis Varoufakis, who resigned Monday, would be announced later in the day after a meeting of political party leaders.

Sakellaridis said Prime Minister Alexis Tsipras "feels the need to thank (Varoufakis) for his ceaseless efforts to promote the government's positions and the interests of the Greek people, under very difficult conditions."

9:50 a.m.

A prominent lawmaker with one of Germany's governing parties says he doubts that the departure of Finance Minister Yanis Varoufakis will make talks on Greece's financial future easier.

Carsten Schneider of the center-left Social Democrats told ZDF television that the resignation is "not so important" and what matters is what policies the Greek government wants to pursue.

Varoufakis, who had annoyed many of his fellow eurozone finance ministers, said he was told that some ministers and other creditors would prefer that he not attend the ministers' meetings.

Schneider said that Varoufakis "can't keep his promises and is drawing the consequences by fleeing." He added that a new minister might create a little more trust, but what is needed is Greek willingness to accept reforms and stabilize the country.

9:20 a.m.

Greek Finance Minister Yanis Varoufakis said in his resignation statement that his decision was made to further the Greek peoples' cause.

"We of the left know how to act collectively with no care for the privileges of office," said Varoufakis, who had become a focal point for friction in meetings with Greece's creditors.

He hailed the "no" vote in the referendum as a victory for democracy that would have global impact.

"The superhuman effort to honour the brave people of Greece, and the famous "oxi" ("no) that they granted to democrats the world over is just beginning," he said Monday morning.

No replacement has yet been named.

8:57 a.m.

Greek Finance Minister Yanis Varoufakis has resigned, saying he was told shortly after the Greek referendum result that the other eurozone finance ministers and Greece's other creditors would prefer he not attend the ministers' meetings.

Varoufakis issued an announcement saying Prime Minister Alexis Tsipras had judged that Varoufakis' resignation “might help achieve a deal” and that he was leaving the finance ministry for this reason Monday.

Varoufakis is known for his brash style and fondness for frequent media appearances at the start of his tenure when the new government was formed in January. He had visibly annoyed many of the eurozone's finance ministers during Greece's debt negotiations.

3:35 a.m.

The final results of Greece's bailout referendum are in, with all 19,159 precincts reporting. The "No" side won with a higher than expected 61.31 per cent, while "Yes" got 38.69 per cent.

A total of 6.16 million Greeks voted in Sunday's referendum, or 62.5 per cent of eligible voters. The poll needed a minimum 40 per cent turnout to be valid.

1:35 a.m.

The president of the eurozone finance ministers' group, Jeroen Dijsselbloem, calls the outcome of Sunday's referendum "very regrettable for the future of Greece."

The Dutch finance minister has over the past five months of negotiations resisted Greece's attempts to get easier terms for its bailout program. He says that "for the recovery of the Greek economy, difficult measures and reforms are inevitable. We will now wait for the initiatives of the Greek authorities."

He says the 19 finance ministers will discuss the outcome of the Greek referendum on Tuesday, the same day a summit of the eurozone leaders will be held.

1:25 a.m.

Upon the request of Prime Minister Alexis Tsipras, Greek President Prokopis Pavlopoulos has convened a meeting of the leaders of the seven parties represented in Parliament.

In a meeting with Pavlopoulos, Tsipras was expected to have presented his plans for negotiating a new bailout deal with the country's creditors.

Pavlopoulos says he accepted Tsipras' demand, saying that the referendum was not about staying in or leaving the euro.

1:00 a.m.

Police say about 100-150 anarchist protesters have started throwing firebombs at riot police and setting trash cans on fire in the central Athens neighbourhood of Exarcheia. This is far from the place where celebrations are taking place by supporters of the "no" vote in Sunday's referendum.

There was no indication that the violence was connected to the political campaigns involved in the vote.

12:45 a.m.

A somber European Parliament President Martin Schulz says a summit of eurozone leaders planned for Tuesday should discuss a "humanitarian aid program for Greece" after Greeks voted to reject demands for more austerity in exchange for rescue loans.

Schulz says in a statement that Athens should make "meaningful and constructive proposals" in the coming hours to get the talks with the other 18 eurozone nations going again. He says: "If not we are entering a very difficult and even dramatic time."

Schulz says ordinary citizens, pensioners, sick people or children in kindergarten should not pay a price for the dramatic situation the country is in, which he blamed the Greek government for. He says the country needs a humanitarian program immediately.

11:25 pm

Germany and France have called for a European Union summit on Tuesday to discuss the Greece financial crisis after the "no" vote won the bailout referendum.

11:05 p.m.

Poland's prime minister says that if final results in Greece's bailout referendum are confirmed as "no," she believes that Greece will have no choice but to leave the eurozone.

Ewa Kopacz said that she suspects that if official results confirm a "no" victory, "the path of Greece can be only one: leaving the eurozone."

Poland has not adopted the 19-member joint European currency. Though it has pledged to adopt the euro in the future, the prospect is very unpopular among Poles and politicians continue to postpone euro adoption.

10:25 p.m.

The head of the socialist grouping in the European Parliament has called for new negotiations with Greece in a spirit of "solidarity and co-operation" after returns show the "no" side leading in the bailout referendum.

Gianni Pittella says that the socialists would "expect the Greek government to come back to the negotiations with a renewed responsible attitude."

He acknowledged the international lenders would also have to show a new approach.

Pittella said Sunday that "it will also be time for some member states and ministers to stop with unacceptable rigidity, national selfishness and domestic political games."

9:30 p.m.

Belgium's finance minister is one of the first eurozone ministers to react to an official projection and opinion polls that the "no" vote will win in the Greece referendum, saying it will complicate matters.

Johan Van Overtveldt insists, however, that the door remains open to resume talks with the Greek government "literally, within hours."

He told VRT network on Sunday that the eurogroup of 19 finance ministers can again discuss measures "that can put the Greek economy back on track and gives the Greeks a perspective for the future."

Greeks voted on its financial future, choosing in a referendum whether to accept creditors' demands for more austerity in return for rescue loans or defiantly reject the deal. Final results are expected later Sunday.

8 p.m.

Greek Finance Minister Yanis Varoufakis is conferring with the country's bankers over what to demand next from the European Central Bank, a ministry spokesman has confirmed.

The spokesman spoke on condition of anonymity pending official announcements. It wasn't immediately clear where the talks were taking place.

According to the head of the Greek Banks' Association, cash is only going to last until Monday.

Although banks are expected to re-open Tuesday, it is almost impossible to have banks open without a large infusion of cash. Greek financial media have reported the Bank of Greece will ask the ECB for 6 billion euros ($6.6 billion) in emergency assistance.

Meanwhile, a close aide to Greek Prime Minister Alexis Tsipras said a "no" vote win should not be regarded as an intention by the government to leave the euro.

It is wrong to link a "no" result to an exit from the eurozone. If a "no" prevails that will help us get a better agreement," Minister of State Nikos Pappas told private Alpha television. - Demetris Nellas.

7:30 p.m.

German Chancellor Angela Merkel will travel to Paris on Monday to discuss the outcome of the Greek referendum with French President Francois Hollande.

Merkel's office said Sunday that she will fly to Paris in the evening for a "joint assessment of the situation after the Greek referendum and to continue the close German-French co-operation on this issue."

Soon after polls closed, Hollande made a similar announcement, saying he would have a working dinner with Merkel on Monday evening to "evaluate the consequences" of the vote.

Earlier in the day, the French economy minister said the German and French leaders had no disagreements when it came to dealing with the situation in Greece.

6:55 p.m.

Spanish Prime Minister Mariano Rajoy says that whatever the result in Greece, its future will be a difficult one.

Rajoy says the eurozone has rules and regulations "to ensure its own survival."

He says that "Europe has always shown its solidarity with Greece, but the euro cannot be an 'a la carte' club in which you can pick and choose."

Rajoy also said Sunday that "Greece needs to grow, create jobs, and to do so it must have policies that work to that effect. Demagogy always ends up crashing into reality."