The euro fell sharply against the dollar following the data, but bounced back to trade higher in mid-morning London trade.
The euro zone-wide data came after preliminary data Tuesday showed that German annual inflation came in weaker than expected in April, rising by just 1.1 percent. Analysts had expected inflation of 1.3 percent in the euro zone's largest economy.
Fears that the 18-country currency bloc was sliding towards deflation were ignited in October when data showed inflation had fallen to a 47-month low of 0.7 percent and the central bank cut interest rates at its November meeting to a record low of 0.25 percent in response.
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Price growth, however, has continued to disappoint and remained well below the ECB's target level of just under 2 percent. This has led to increasing calls for ECB President Mario Draghi to boost the region's economy - and the latest inflation data is likely to heighten expectations of some action from the central bank on May 8.
"We would argue this bounceback in annual CPI (consumer price inflation) in the wake of March's soft print is small enough to ensure there is continued speculation of further ECB policy support but not so small as to guarantee a change in stance at the very next meeting," Rabobank strategists said in a note Wednesday.
"Neither will these numbers do much to refute Draghi's widely reported comments earlier this week that while the ECB is ready to embark upon QE (quantitative easing), such a program is not imminent."