ATHENS--Greece's leading lender, the National Bank of Greece (ETE.AT), has completed its long-awaited capital increase, raising enough money from private investors to avoid a complete nationalization by the state.

The lender said Friday that 10.8% of the 9.7 billion euro ($12.9 billion) capital hole it needs to fill came from private investors amid solid interest from investors abroad. The remaining amount will come from Greece's bank rescue fund.

"About 50% of the increase was covered by capital from abroad, resulting in the inflow of investment capital to Greece of EUR500 million," it said in a statement.

As part of Greece's latest bailout by its euro-zone peers and the International Monetary Fund, EUR50 billion has been set aside to recapitalize the country's four big banks and restructure another half dozen state and private lenders.

Under the terms of the recapitalization plan, the banks must secure 10% of their capital needs from the private sector to maintain management autonomy and avoid becoming fully state controlled. Greece's bank rescue fund will underwrite the balance, but will have only restricted management rights if its share is less than 90%.

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

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