Economists polled by Reuters had forecast that the annual consumer price inflation rate would drop to 8.4% in May, moving further away from October's 41-year high of 11.1%.
"May's CPI figures ratchet up the pressure on the Monetary Policy Committee to increase Bank Rate substantially further over the coming months," Samuel Tombs, chief UK economist at Pantheon Macroeconomics, said.
Food and drink price inflation dropped slightly to 18.3% from April's 19.0%.
The BoE is widely expected to raise interest rates on Thursday to 4.75% from 4.5%.
After Wednesday's data, markets fully priced in interest rates reaching 6% by December - up from around a 50% chance of such a move on Tuesday.
Persons:
Henry Nicholls, Samuel Tombs, Sterling, BoE, Grant Fitzner, . Paul Dales, Rishi Sunak, Jeremy Hunt, Andrew Heavens
Organizations:
Bank of England, REUTERS, Bank of, Reuters, Monetary, Committee, Pantheon, U.S ., National Statistics, ., Capital Economics, Bank, Fed, ECB, Thomson
Locations:
City, London, Britain, Bank of England