ATHENS--National Bank of Greece SA (NBG), the country's leading lender, turned a profit in the first half of the year, boosted by gains from international operations and lower provisions for bad loans at home.

The bank reported a net profit of EUR344 million versus a loss of EUR1.9 billion in the same period a year earlier. For the second quarter of 2013, NBG postd an adjusted net profit of EUR126 million.

With the country in its sixth year of recession, NBG booked EUR853 million in losses on sour loans, down 29% year-on-year.

The bank, which had expanded into neighboring markets before the country's debt crisis erupted three years ago, said that operations in southeastern Europe were starting to turn profits. Its Turkish unit Finansbank added EUR180 million to the bank's core profitability.

"NBG has the comparative advantage of its significant presence both in Turkey and Southeast Europe, dynamic regions that enable it to diversify its sources of income, thus adding substantial value to the group," said CEO Alexandro Tourkolias in a statement.

"Our second quarter performance adds to the more optimistic climate. In particular, the group's core profitability was positive for a third consecutive quarter, pointing to a return to healthy results, a necessary condition for sustainable growth."

Net interest income, a measure of the bank's core revenue, fell 9% year-on-year to EUR1.6 billion.

Like other Greek lenders, NBG said that it has improved its funding mix and reduced its reliance on emergency loans from the Greek central bank, which fell below the one billion mark at the end of August.

Write to Stelios Bouras at stelios.bouras@dowjones.com

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