David Cameron has said he will "make no apology" for spending more than £9 million of taxpayers' money on a pro-EU publicity drive ahead of the referendum on Britain's future membership.
Pro-Brexit campaigners have reacted with fury to the decision to send a Government-produced leaflet to every household in the country setting out the case for a "remain" vote on June 23.
Downing Street said the move was a response to polling which showed 85% of the public wanted more information from the Government to help them make an informed choice on June 23.
But opponents said it was a waste of public money which breached ministers' assurances that the Government would not seek to play a significant role in the campaign and unfairly skewed the debate.
The cost of the promotional push was greater than the £7 million each the formal Leave and Remain camps will be allowed to spend by law in total during the last 10 weeks of the campaign, Vote Leave complained.
But the Prime Minister told a rally of young people in Devon: "I make no apology for the fact that we are sending to every household in the country this leaflet which sets out what the Government's view is and why we come to that view.
"We are not neutral in this. We think it would be a bad decision to leave. We think it would be bad for our economy, bad for jobs, bad for investment, bad for families' finances.
"We think it would be bad for universities. We are not neutral so we have made a clear stance in this leaflet which everyone will get a copy of."
He warned young people they had "the most to lose" from the UK leaving the EU.