The EU-harmonised consumer price inflation rate rose to 3.6% in April, from 3.5% in March.
Meanwhile, the nationally based consumer price index fell to 3.1% from 3.4% in March 2012 and 3.3% in April 2011.
Compared with the previous month, the consumer price index increased by 0.88%. The Statistical Service said this was owing to increases in the prices of certain clothing and footwear items, electricity and petroleum products.
Decreases were recorded in the prices of certain fresh vegetables and fresh lamb.
For the period January-April 2012, the CPI rose by 3.2% compared with the first four months of 2011.
Eurostat has changed the rules on weighting for the harmonised index, which will now be based on national accounts data, rather than the household budget survey.
The main change will be a bigger weight for accommodation services.
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