The Bank of England had already said it expected inflation to fall below 1 per cent and remain there for months to come.
The fall was driven by lower oil prices and household energy bills remaining flat compared with December 2013, when they rose sharply.
Officials want to avoid a downward spiral of falling prices, with consumers putting off spending and firms delaying investment.
The latest inflation figures come during an important week for economic data, with employment and wage numbers out tomorrow and public sector finance figures – giving a key update on efforts to bring down the deficit – on Friday.
But TUC general secretary Frances O’Grady said: “Low inflation is a sign of fragility in both the UK and global economy.”
Shadow Treasury minister Cathy Jamieson said: “Wages continue to be sluggish and working people are £1,600 a year worse off under this government. A few months of falling world oil prices won’t solve the deep-seated problems in our economy.”