Tories play glamour card by wielding Caine

David Cameron said he hoped the voluntary two-month programme – that could include team-building tasks and helping in the community – would become universal and help cure the "national scandal of all this wasted promise".

The Tory leader, who said he had ruled out making the scheme compulsory because that would defeat its impact, was joined on stage by Sir Michael as he sought to bring a touch of Hollywood glamour to the Tory campaign.

Sir Michael, who grew up in a poor area of south London, admitted he had hated military service as a youngster but said this scheme – which the Tories have already piloted in several areas – would provide an opportunity to "save young people and give them a chance in society".

Mr Cameron said extended pilots, which would seek to bring youngsters from different backgrounds together, would be funded by diverting 50m from the Government's preventing violent extremism programme which has been criticised for alienating Muslim communities. Opponents, however, said the nationwide move was unfunded.

Labour's Schools Secretary Ed Balls said it was "yet another spending commitment from the Tories with the flakiest of funding solutions", while the Liberal Democrats said the Conservatives had made "an enormous spending commitment without the foggiest idea of how they're going to pay for it".

Mr Cameron said he wanted the scheme to be "one of the proudest legacies" of a Tory government.

Aides said schemes could include a full-time residential week of "team-building" activities basis, followed by a week developing skills and helping groups in their own communities.

Youngsters would then live at home for the remaining six weeks, designing and carrying out a social action programmes.