Caine stars in the Etonian job

Moves to recruit a citizen's army of teenagers to carry out community work were spelt out by David Cameron at the first Conservative press conference of the campaign.

He was joined at the policy launch by the actor Sir Michael Caine, who said it would reach out to a "very, very hard core of people who we've got really to save". Mr Caine, who last year threatened to leave Britain for America if income tax rose any higher, grew up in Elephant and Castle, a deprived area of south London.

Under the plans, 16-year-olds would spend two months volunteering with a National Citizen Service, where they would help in their community.

Mr Cameron stressed that the programme would not be compulsory. But he claimed it would be so attractive to youngsters that eventually every 16-year-old would want to take part. It would be funded by scrapping government community cohesion schemes.

Mr Cameron said: "This non-military national service will transform the lives of millions, giving them purpose and shape and a sense of direction."

His wife, Samantha Cameron, went out campaigning solo for the first time yesterday, visiting a Christian charity for the homeless in Cookridge, Leeds, before being shown around horticultural and woodwork projects.

She helped pot plants in a greenhouse and restricted her comments to "It's so beautiful here" and "I hope to highlight the amazing work charities like this do for some of the most vulnerable people in society, who tend to fall through the net."