Greece strikes deal on austerity plan, Samaras says

(CNN) -- Debt-stricken Greece has agreed on final details with its international creditors on the terms for the next installment of a bailout deal, the prime minister said Tuesday.

However, the agreement on new austerity measures and the country's budget must still be approved in two parliamentary votes -- which are likely to test the strength of Prime Minister Antonis Samaras' governing coalition.

Samaras said Greece's representatives had done "everything possible" in their negotiations with the so-called troika, the European Commission, the European Central Bank and the International Monetary Fund.

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"We exhausted all possibilities, pressures and time. We achieved important improvements, even at the last moment," Samaras said. "As long as this agreement is approved and the budget voted into approval, Greece will remain in the euro and will find its way out of the crisis."

The Greek government has until now struggled to nail down all of the €11 billion of spending cuts it needs to satisfy the conditions of its international bailout.

The harsh austerity measures already in place have angered many people in Greece, which is in its fifth year of recession and has seen its unemployment rate soar to more than 25%.

Greece's parliament is under pressure to pass the new austerity package before November 12, when eurozone finance ministers are expected to announce whether they will release the money.

The first parliamentary vote -- this one on the budget -- is expected Wednesday, with the second vote, on reforms and austerity measures, scheduled for Monday.

Samaras warned that the danger for the Greek people going forward did not lie in which measure was or wasn't passed, but rather in what might happen if the agreement was not approved and the nation plunged into chaos.

"These dangers must be avoided. And that is now the responsibility of all parties and of every member of parliament individually," he said.

The coalition headed by Samaras is made up of his center-right New Democracy party, the socialist party Pasok and the Democratic Party of the Left, or DIMAR.

While Pasok has not yet commented, it seems Samaras may struggle to bring the Democratic Left on board.

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"DIMAR fought for labor relations with specific positions in order to protect already weakened labor rights," the party said in a statement Tuesday. "We don't agree on the outcome of the negotiations. DIMAR maintains its position."

Radical leftist party Syriza also voiced opposition to the austerity package -- and urged people to take to the streets to demonstrate against its passage.

"Government measures should not be voted into effect, they will not be implemented," a statement said. "Public protests are the only effective answer to the plans to demolish the rights of workers and of young people (that) will mean the subordination of the country to its lenders and to big capital."

Greece, and particularly Athens, has seen repeated street demonstrations against the austerity measures imposed on the nation, some of which have turned violent.

Two general strikes have been called in recent weeks by unions who say that another round of cuts to wages and pensions will be too painful for the Greek people to bear.

Critics of austerity argue that the country needs measures to promote growth and create new jobs.

Samaras said he was already pushing for Greece to be given more than the 31 billion euros expected in the latest installment of funds "so that there is a significant effect on the real economy."

Greece's long-running economic woes have shaken global markets and led to fears it could crash out of the 17-member eurozone single currency if it defaults on its debt.

The turmoil in the eurozone has exacerbated concerns about other ailing nations such as Spain and Italy, which are also struggling with high unemployment and debt.

CNN's Christine Theodorou and Diana Magnay contributed to this report.