Annual food inflation jumped to 3.6 percent from 2.9 percent the previous month. Non-food price inflation was steady at 0.5 percent in the year to May, unchanged from April.
Transport costs fell 1.3 percent, but hotels and restaurants were 2.8 percent more expensive, the agency said without giving details.
On a month-on-month basis, the consumer price index rose to 0.5 percent in May, up from 0.1 percent in April as food price inflation rose 0.8 percent.