ATHENS — Four of Greece’s leading banks are to receive a $23 billion capital injection to replenish reserves which were hit by the country’s massive debt restructuring deal. The country’s Financial Stability Fund said Wednesday it had approved the funds’ release.

The $23 billion will be split between the National Bank of Greece, Eurobank, Alpha Bank, and Bank of Piraeus as part of a $64 billion recapitalization plan to boost their liquidity levels and keep them in business — a key element of the second, $166 billion bailout agreement that Greece had negotiated with the European Union and the International Monetary Fund last March to stay solvent.

Greek banks suffered massive losses following a write-down of their Greek government bond holdings this year.

On top of the write-downs, Greek banks have also been hit by customers withdrawing their euro-denominated savings as they hedge against the country’s possible forced exit from the single currency and a return the drachma.

An official at the stability fund told the Associated Press the bank payments should be concluded in the “next two days.’’

The official said the National Bank would receive $8.73 million, Piraeus Bank $6.33 billion, Eurobank $5.32 billion, and Alpha Bank $2.41 billion.