The annual rate of inflation in the 18 countries that use the euro was unchanged at 0.4% in August, as the European Union's statistics agency revised a previous estimate that recorded a decline to 0.3%

However, the annual rate of inflation in the eurozone remained at the lowest level since Oct 2009.

The latest figures released by Eurostat also showed that the annual rate of inflation across the 28-member EU fell to its lowest level since Oct. 2009 in July, and was unchanged in August, an indication that very muted price rises threaten the economic recovery beyond the borders of the eurozone.

The EU's statistics agency Wednesday said consumer prices in the eurozone were 0.1% higher than in July, and 0.4% higher than in August 2013. That revised the preliminary estimate for the annual rate of inflation of 0.3% released late last month.

Eurostat also said the annual rate of inflation in the broader EU--which includes 10 countries that don't use the euro--was unchanged at 0.5% in August, having been revised lower to that figure in July from a first estimate of 0.6%.

Eurostat's figures show that six eurozone members experienced declines in prices in the 12 months through August, while two members of the EU that don't use the euro shared the same experience. But other members were on the cusp, with three eurozone members recording inflation rates below 0.5%, as did five EU members that don't use the common currency.

The slowdown in inflation is a mixed blessing. While it has helped boost real incomes at a time of weak wage growth, it also makes it more difficult for governments and households to cut their high debt levels, a particular problem in southern Europe, where unemployment is also very high.

More worryingly for policy makers, there is a risk that an unanticipated economic setback could push some economies into deflation--a sustained and self-reinforcing fall in prices--gjven the very low levels of inflation.

Earlier this month, the ECB responded to inflation rates that seem likely to remain well below its target of just below 2.0% by cutting its key interest rates and announcing two new programs to asset-backed securities and covered bonds.

However, the Organisation for Economic Cooperation and Development Monday said that may not be enough to boost growth and inflation, and called on the ECB to launch a program of large scale asset purchases, including government bonds.

"Recent ECB action is welcome but further measures, including quantitative easing, are warranted," said Rintaro Tamaki, the OECD's acting chief economist.

Faced with similar problems, other European central banks also seem likely to maintain easy monetary policies in coming months. Sweden's Riksbank cut its benchmark interest rate in July, and although it left policy unchanged earlier this month, also indicated that rate won't be raised for about a year.

Poland's central bank has indicated it is likely to cut its benchmark interest rate, possibly as soon as its next meeting in October. The Czech National Bank has said it would extend its weak-koruna policy well into 2016 to tackle low inflation, while Hungary's central bank cut its key interest each month for two years through July, and now intends to keep borrowing costs low for a long time.

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