(CNN) -- The International Monetary Fund on Sunday approved a 30 billion euro ($38.6 billion) loan for Greece as part of a larger European Union-led effort to help ease the country's economic crisis.

The three-year deal makes about 5.5 billion euros (US $7 billion) immediately available to Greece's battered economy, the IMF said in a statement announcing the loan.

The approval comes a week after Greece accepted an international aid package -- negotiated by the IMF, European Central Bank and European Commission -- worth 110 billion euros (US $141 billion).

On Sunday, Greek Prime Minister George Papandreou blamed the economic crisis on corruption "on all levels."

"The same economic crisis that we're living through is proof that these phenomena drove our country to unbearable debt and deficit and stagnated development," Papandreou said in a statement.

"That is why it is our obligation to improve, with all of our might, how the political system operates and for society to not shape a general climate that is against that system and against the institutions which can ultimately only harm the country and citizens themselves."

Clashes between police and thousands of demonstrators in Athens on Thursday killed at least three people. The demonstrations came hours after Greek lawmakers approved an unpopular package of budget-cutting measures. The measures were required to meet the terms of the EU bailout.

Papandreou called for a meeting of Parliament on Monday to address the issues.