Some bankers are optimistic that interbank lending will recover. A banker in one particularly weak eurozone country, who declined to be identified because he was discussing confidential bank information, said that it was already much easier to find cash on the interbank market. He credited the improvement to E.C.B. policies, and said he expected interbank lending to increase in coming months.
But banks remain reluctant to lend the cash on to businesses, the banker said. Many borrowers remain too risky.
In addition, banks are behaving cautiously right now as the E.C.B. conducts what is supposed to be the most rigorous scrutiny of their books ever. The central bank is scheduled to complete the comprehensive review of the largest eurozone banks by the end of October. Lending could pick up once banks know where they stand.
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There is hope, though, that another central bank measure—also taken in June—could end a long drought of credit in crisis countries like Greece, Italy and Portugal. After its June meeting, the central bank announced a program to provide cheap lending to banks, on the condition that they lend the money to businesses or to individuals.
The E.C.B. is to begin dispensing that money on Sept. 18, and most analysts expect the central bank to see how many banks take advantage of the offer before it takes any additional stimulus steps like quantitative easing.
One clear set of beneficiaries of ultralow interest rates is eurozone governments.
Only a little more than two years ago, there was fear that Spain and Italy would go bankrupt because of their rising borrowing costs. Investors now accept almost the same return on Spanish and Italian 10-year bonds as they do on United States Treasurys.
On Monday, Spain sold 1 billion in bonds maturing in 50 years at an interest rate of 4 percent. Spain plans additional bond issues later this week.
Spain and other eurozone countries are cashing in on the perception that the European Central Bank will not let them fail. That is why investors can harp about what they see as the ineffectiveness of President François Hollande of France and his Socialist government, then buy French debt at almost absurdly low rates.
''It's a paradox,'' said Christian Jimenez, president of Diamant Bleu Gestion, an asset management firm in Paris. ''French debt is protected by potential action of the E.C.B.''
Mr. Jimenez added, though, that his firm was betting against French bonds in the market on the expectation rates will have to rise again. ''It's a good period for issuers,'' he said, ''but it's very bad for the economy.''
—By Jack Ewing of The New York Times