The number of young people in the UK without a job rose 156,000 in the three months to July, according to new data.
The Office for National Statistics said those aged between 16 and 24 saw the biggest drop in employment compared with other age groups.
Overall, the UK's unemployment rate grew to 4.1% over the period, compared with 3.9% previously.
Firms continued to remove staff from payrolls as they prepared for the end of the government's furlough scheme.
Some 695,000 UK workers have disappeared from the payrolls of British companies since March, when the coronavirus lockdown began.
ONS director of economic statistics Darren Morgan said: "With the number of employees on the payroll down again in August and both unemployment and redundancies sharply up in July, it is clear that coronavirus is still having a big impact on the world of work."