By Claire West

Almost half of British adults could not identify the size of the national public debt in a survey of more than 2,000 UK residents commissioned by London PR agency TopLine Communications to understand how well government is communicating one of its biggest issues.

When presented with four options, 55% put the debt at the then correct figure of £815 billion (to July 2010) and 24% of the sample considered the national public debt to be no more than £815 million, a tenth of the true value.

Almost a fifth - 18% - thought we owe £815 trillion, and an astonishing 3% believed this to be a mere £815 thousand.

Heather Baker, Director of PR at TopLine Communications, comments: "These results are illuminating and highlight the need for the government to communicate better with the public. If claims that David Cameron is worth millions are to be believed, one questions whether 3% of the population is scratching their heads wondering why he hasn't paid off the national debt out of his own pocket!

"With the Comprehensive Spending Review only hours away, we hope that Mr Osborne will leave enough for departments such as the Treasury and the Office for National Statistics to focus on a communications campaign to clear up some of the confusion."