British consumer price inflation fell slightly faster than expected in May, helped by lower food costs and boosting hopes that April's 17-month high marked a peak.

The Office for National Statistics said that the annual rate of CPI inflation fell to 3.4 percent in May from 3.7 percent in April, a somewhat bigger drop than the fall to 3.5 percent forecast by economists.

The decline was driven by a fall in food prices on the month – especially those of grapes — as well as slower rises in the price of petrol, alcohol and tobacco than the same month last year.

The news will be welcomed by the Bank of England, which last month had to write a public letter explaining why inflation had stayed so far above its 2 percent target for so long.

On the month, consumer price inflation rose by 0.2 percent, a third the 0.6 percent rate recorded in April and less than the 0.3 percent increase expected by analysts.

The retail price inflation gauge, used as a basis for some wage deals, fell to 5.1 percent on the year from 5.3 percent, versus forecasts for an easing to 5.0 percent. Housing costs — which have a higher weight in RPI than in CPI — rose by 3.5 percent, their fastest pace since May 2008.

Food costs in the CPI index were down 0.1 percent on the month and showed their smallest annual rise since February.

The core rate of CPI, which excludes volatile food and energy costs, also fell to its lowest rate since February at 2.9 percent on the year.