Between October and March, government advertising rose by 35% making it ITV's fastest-growing client.
However, the figures are just one in a lengthening list revealing how government adspend has soared in the months running up to the election. In April, it was announced that the government was the UK's largest advertiser and had surpassed spend of the world's two largest advertisers, Unilever and Procter & Gamble.
Leading opposition figures have accused the government of wasting taxpayer's money on awareness campaigns for pensions, holiday entitlements and the minimum wage. Television ads have also been used to recruit nurses and policemen and discourage drink driving.
A source within Whitehall said government advertising must adhere to strict impartiality rules and provide value for money. "The advertising is not political or about promoting any party. It's about communication of public information rights and responsibilities," the source said.
The figures contrast sharply with ITV's other advertisers, most of which have cut spending amid concern over the world's economy despite ITV commanding 38% of the peak-time audience.