The Chancellor set out measures to tackle growing unemployment among younger people.
From next month, no one aged 18 to 24 needs to be unemployed for longer than six months without receiving an offer of a job, work-related training or a work placement. The guarantee was initially set at 12 months.
Every 16 or 17 year old school leaver is to be guaranteed a place in education or training again next September.
A special fund will provide £8 million of financial help for 10,000 undergraduates from poorer backgrounds, enabling them to take up short, unpaid internships in industry and the professions.
To help older workers in part-time jobs, the minimum number of hours those aged 65 must work in order to be eligible for tax credits is to be cut.