The Ministry of Defence wastes up to £94 million a year training 16 and 17-year-old army recruits for roles which could be filled by adults, campaign groups have said.
According to a report by Child Soldiers International and ForcesWatch, it costs as much to train a 16-year-old as an 18-year-old.
More top news
A mother feared to have been planning to travel to Syria with her four children has been arrested after returning to the UK.
Labour leadership contender Yvette Cooper has accused Jeremy Corbyn of not being straight with people over the economy.
Most of Britain to remain dry and cloudy.