Rishi Sunak said parents are worried about what their children get up to at the weekend and on evenings – and national service will provide them with "rules and structure".
Rishi Sunak has argued national service will "keep kids out of trouble" – and lots of parents are "worried" about what their children get up to at the weekend.
The plan, which has faced criticism from some Tory ministers, would see 18-year-olds given the choice of a full-time military placement for 12 months, or a scheme to volunteer for one weekend a month for a year.
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At a campaign event in Stoke-on-Trent, a mother of two in favour of the policy asked the prime minister if it should be broadened to include ex-convicts who could benefit from "the rules and structure national service provides".
Mr Sunak did not answer the question directly but said it would be "transformational" for teenagers by providing them with "skills and opportunities… some structure, some rules".
The Tory leader added: "I think it will be really brilliant for young people to have this rite of passage that they go through with everything that it teaches them and just keeps them out of trouble.
"I've talked to so many parents worried about what their kids are doing in the evenings, at the weekends.
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"So I think this will be wonderful for young people, but I also think it'll be great for our country."
Under the plan, due to be fully in place by 2029-30 if Mr Sunak wins the election, all 18-year-olds will be legally required to take up either a 12-month placement in the Armed Forces or cyber defence – or give up the equivalent of one weekend a month to volunteer in their communities.
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The £2.5bn policy was the first major announcement of his campaign, but it has been met with a backlash and even ridicule by both his own MPs and political opponents.
Northern Ireland minister Steve Baker, who is currently on holiday in Greece, publicly criticised the way the policy had been "sprung" on Tory candidates and hinted at unease over the idea.
"History has proven time and time again that liberty under law – not compulsion and planning – is the surest road to peace and prosperity," he said.
Questions have also been raised over how the plan would work in practice and whether parents or children would be punished if they refuse to take part.
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Home Secretary James Cleverly has told Sky News that "there's going to be no criminal sanctions, nobody's going to jail over this".
Foreign Office minister Anne-Marie Trevelyan suggested parents could be fined, comparing the compulsory nature of national service to young people having to attend school until they are 18.
But on Tuesday morning, Work and Pensions Secretary Mel Stride suggested that this will not be the case.
Asked by LBC what sanctions parents could face, he said: "Clearly none because this relates to an adult who is 18 years old and it is their responsibility to engage with the programme."
The final details are expected to be fleshed out following a Royal Commission that will look into what incentives to offer for people who engage and what sanctions to put in place for those who don't, ministers have said.
The plans have been attacked by Labour, with Sir Keir Starmer calling it a "teenage Dad's Army".
