The increase, revealed this week in the COI's annual report, took total advertising spend on public information campaigns to £189.5m in the 12 months to March 31 2004, an increase of £29m on the previous year.
Last year's spend was just £40m less than that of the UK's biggest advertiser, Procter & Gamble.
Conservative Party chairman Dr Liam Fox said he was astounded by the size of the increase. "We now have a government which is believed by voters to be profoundly dishonest. What makes matters worse is that it is using increasing amounts of taxpayers' money to spin its half-truths and deception."
The news came in the same week as the start of a controversial £8.3m campaign to help the public cope in the event of a terrorist attack. It follows a similar initiative in Australia, which has been criticised for stating the obvious and being a waste of public money.
The UK activity includes TV ads and a brochure being sent to households.
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