The increase means inflation has returned to the levels seen in the six months between October 2012 and March 2013 despite a brief slowing to 2.4 per cent in April.
The largest upward contribution came from air transport and motor fuels and clothing while the largest downward contribution came from food.
Transport rose by 0.4 per cent between April and May compared to a fall of 0.8 per cent between the same period a year ago. Air fares rose by 22 per cent while petrol and diesel fell overall but by less than a year ago.
{desktop}{/desktop}{mobile}{/mobile}
Clothing and footwear rose by 1.2 per cent compared to a fall of 0.1 per cent between the same period a year ago. The ONS said prices for woman's outerwear increased due to the unseasonal cold weather in May.
Prices for food and non-alcoholic beverages were unchanged between April and May compared to a rise of 0.3 per cent in the same period last year.
CPIH, a new CPI measure which includes the cost of owner occupiers housing costs, was 2.5 per cent, up from 2.2 per cent in April.
RPI inflation, which includes mortgage payments, was 3.1 per cent, up from 2.9 per cent in April.

• Want to receive a free weekly summary of the best news stories from our website? Just go to home page and submit your name and email address. If you are already logged in you will need to log out to see the e-newsletter sign up. You can then log in again.