By DAVID JOLLY
PARIS — Greece’s debt rose to 159.1 percent of its gross domestic product in the third quarter of 2011 from 138.8 percent a year earlier, according to data released Monday that illustrates the country’s worsening economic straits after two years of austerity budgets.
The data, reported by the European Union statistics agency Eurostat in Luxembourg as part of a new series, underscored the urgency of the talks continuing Monday in Athens, where Greek officials and international lenders were trying to reach agreements that would make possible the release of new financing to stave off a Greek default next month.
It was the realization in late 2009 that Greece had been hiding the true state of its public finances that set the European sovereign debt crisis in motion and left the future of the euro currency itself in jeopardy.
Two years of austerity measures have weighed on employment, with the jobless rate at 19 percent, and hurt government tax revenues. The economy is expected to show a contraction of 6 percent in 2011, the International Monetary Fund has estimated.
Shrinking the G.D.P. side of the equation makes it harder to bring down Greece’s debt ratio to a more manageable level, and adds pressure for additional taxes and spending cuts.
The E.U. has forecast Greece’s debt ratio for 2011 at 162.8 percent — far above the 60 percent that euro zone members are supposed to aim for. Negotiators are hoping to put the Greek economy on a footing that would bring it to 120 percent of G.D.P. by 2020, but even that figure is now in doubt.
Eurostat also said the debt ratios of the 17 euro zone nations as a whole rose to 87.4 percent of G.D.P. from 83.2 percent a year earlier. For all of the 27 European Union nations, the debt ratio rose to 82.2 percent from 78.5 percent.
Those averages remain below the roughly 100 percent for the United States and 200 percent for Japan.
Among the most indebted euro members, Italy’s debt ratio rose 0.5 point to 119.6 percent in the third quarter from a year earlier, though it did show progress in shaving down by 1.6 points from the second quarter of 2011. Portugal’s debt ratio rose 18.9 points from a year earlier, to 110.1 percent, while Ireland’s rose more than 16 points to 104.9 percent.
Eurostat, which had not issued such quarterly debt figures before, said the report was meant to complement annual data it already publishes.