Greece's economic slump deepened in the third quarter, with output shrinking 7.2% on an annual basis as the debt-racked country heads into its sixth year of depression.

The contraction was deeper than the second quarter's 6.3% drop.

It follows the passage of a tough 2013 budget by Prime Minister Antonis Samaras's government that is expected to continue to smother growth for most of next year.

Since 2009, Greece's economic decline has wiped a fifth off economic output and put one in four Greeks out of work.

Analysts said the reading could point to an even grimmer outlook because it was offset by better-than-expected returns from the country's vital tourism sector.

In its mid-term fiscal plan, the government expects the economy to shrink 6.5% in all of 2012 and 4.5% next year. It forecasts a slight recovery to begin at the end of 2013 and growth of 0.2% in 2014.

Greece's prolonged slide has undermined Athens' ability to hit targets laid out in its bailout programme by undercutting budget revenues and feeding popular anger over belt-tightening.

The country of 11 million is awaiting the release of more than €30 billion in aid from its international lenders to pay off debt and shore up its banking sector. But a public clash yesterday between the lenders over how Athens can bring its debts down to a sustainable level reignited fears that its and Europe's broader debt troubles could flare up anew.

Conditions could worsen under the 2013 budget, which includes more than 9 billion euros in new tax hikes and spending cuts, the latter of which will fall most heavily on pensioners and public sector workers.

Bank lobby chief praises Greek austerity

The head of an international banking lobby has praised Greece's recently approved austerity package, and said it provides a "comprehensive framework for reform."

Charles Dallara, managing director of the Institute of International Finance, said Greek governments had shown "impressive willingness to bear short-term pain for long-term gain" in passing a major round of new cuts. They were approved last week and are worth €13.5 billion.

Dallara led negotiations with Greece earlier this year to restructure the country's debt held by the private sector, wiping some €100 billion off the national debt.

Speaking at a banking event in Athens, Dallara said the euro zone countries need to find a better balance between austerity and growth, with an over-emphasis on cuts causing the risk of a "protracted era" of recession or low-growth.