Constancio said the latest data had not altered the central bank's forecast of 1 percent inflation over the course of 2014, but that it was eyeing the situation closely.
"The expectation is we are now seeing a sort of bottom (in inflation), but we have to be sure of that," he said. The ECB aims to maintain the inflation rate at just below 2 percent.
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Constancio also repeated Draghi's message Thursday that the ECB's Governing Council was agreed in its commitment to use methods beyond the conventional interest rates to stimulate the euro zone's economy.
The vice-president confirmed that a ECB bond-buying, or quantitative-easing (QE), program had been discussed, although not in detail.
"We did not discuss details (of QE) because that was not the environment to do it," he said. "We have had some discussions (in the past) and we will have more, about the details... of course, the details are important."
Draghi has repeatedly said there are other policy tools the ECB could use -- and some of the more unconventional measures have recently garnered attention.
Ahead of April's monetary policy decision, Germany's Bundesbank President Jens Weidmann stoked speculation by saying QE had not been ruled out. Unlike central banks in the U.K., U.S. and elsewhere, the ECB has not launched a bond-buying program. Such a move would be a controversial shift in policy and fraught with difficulty as there is no single euro zone bond and the ECB is prohibited from helping out individual governments.