Social Development Minister Ann Tolley said National would help more young people become drug free, move off the benefit and get a job to help ensure they reached their potential.
Only 10% of young people who went on to a jobseeker's benefit stayed for more than six months. But for those who did, their average time on a benefit was almost 10 years.
''We want to invest early and give them one-on-one support so they can develop the skills they need to move into the workforce.''
One in five beneficiaries said drug use was a barrier to them getting a job. National would increase the support to help them kick drug use and get work-ready, Mrs Tolley said
However, National would place obligations on those who did not take up the significant opportunities available in New Zealand to start work or training.
As well as the 50% cut to a benefit for failing to meet their obligations, there would be further reductions if that continued, she said.
''This will also apply to those who continue to fail recreational drug tests where these are requested by prospective employers.''
The lower benefit payments could only be used for essential needs such as rent and food, as happened at present with the Government's money management programme for 16 to 19-year-olds, Ms Tolley said.
Any benefit reductions would be made at the discretion of Winz staff, taking into account individual circumstances. Once individuals decided to meet their obligations, benefits would be reinstated.
Otago-Southland Employers' Association was supportive of investing in young people early, and providing pathways for them to transition to the workplace, chief executive Virginia Nicholls said.
''It makes good sense to employers that young people receive training to increase their skill set, along with the opportunity of one-on-one mentoring.''
Businesses had expressed concern about positive drug tests from some prospective employees. If drug use had been identified, employers were supportive of the provision of rehabilitation services before those people entered the workplace, she said.