Official data Wednesday showed consumer prices rose by an annual 3.2%, down from a 3.4% increase in February.
That was its lowest level in two and half years, but the country's central bank and analysts had forecast marginally lower.
The update means a first interest rate cut by the Bank of England could be further off than previously thought.
And investors reduced their bets on the bank making a move.
They fully priced in only one quarter-point cut by the end of 2024, possibly as late as November.
The slowdown in the fall in Britain's inflation rate follows an acceleration of headline price growth in the U.S.
Analysts said Wednesday's data showed Britain's fight against inflation was not yet won.
With some warning there was a risk that the country will follow the trend in the U.S. and stay elevated.
Services inflation, which policymakers watch closely, eased only slightly to 6% from 6.1%.
The statistics office said a slowdown in food prices was the main contributor to the decrease in headline inflation.
But rising fuel prices slowed the fall in the headline rate.
International oil prices climbed last month due to growing tensions in the Middle East.
