The annual core inflation — which excludes volatile energy and fresh food prices — slowed slightly to 1.7 percent from 1.8 percent in the previous month, the National Statistics Institute (INE) said in a statement.

The figures confirm preliminary inflation date released by the institute on March 30.

Prime Minister Jose Luis Rodriguez Zapatero said early this year that inflation was a worry but he anticipated an easing in the months ahead as oil prices declined.

But political upheaval in north Africa and the Middle East in past weeks has sent oil prices soaring back to levels last seen in mid-2008, stoking fears that they will push rising inflation even higher.

Last month the Bank of Spain raised its inflation forecast for the year to 2.9 percent from 1.7 percent previously. It predicts the inflation rate will fall to 1.5 percent in 2012.