Neets are not in employment, training or education
The proportion of young people in England not in education, employment or training has increased to more than one in 10, government figures show.
At the end of 2007, 9.7% of 16 to 18 year olds were considered to be such "Neets", but by the end of 2008, this had risen to 10.3%.
The increase is being driven by reduced job opportunities for 18 year olds.
But the government says a record number of this age group - 1.61 million - were in education or training.
The statistics, released by the Department for Children, Schools and Families, show that the proportion of so-called "Neets" has fallen for 16 and 17 year olds - who are increasingly likely to stay in education and training during the recession.
At the end of 2008, 92.7% of 16-year-olds and 83.5% of 17-year-olds were in full-time education or training.
The declining number of Neets among 16 and 17 year olds will eventually be removed entirely when the leaving age for education and training is raised to 18.
However the latest overall Neets figure has been pushed up by a substantial increase in 18 year olds not in jobs, training or places in education.
There are now 16.6% of 18 year olds who are classified as Neets - up from 14.2% in the previous year. This age group also faces problems with a pressure on university places this autumn.
The drive to reduce the number of youngsters not in jobs or education is part of the government's efforts to create a better-qualified and higher-skilled workforce.
But in the present economic climate, the Children's Secretary Ed Balls said it was important to prevent the "economic and social scarring" caused by previous recessions - saying that people could not be left to "languish on the dole".
He said that there had been "devastating" consequences for families affected by long-term unemployment and for those lacking in skills to get jobs.
Iain Wright, the minister for 14 to 19 reform and apprenticeships, said that he had memories of people of his own age in the early 1990s who had been "sitting on the dole" - and there needed to be a "different mindset" in this recession.
Children's charity Barnardo's said the situation for young people leaving school at 16 and wanting to work or train in the workplace was "desperate".
Chief executive Martin Narey said the proportion of Neet young people had hovered around 9-10% of the age group for the past decade.
He added: "But beneath this, there are two clear trends: a steady rise in the number of young people staying on in full-time education, and the steady decline in employment and work-based learning opportunities for young people aged 16-18.
"We urgently need a more relevant education system - with more vocational options for young people who are not suited to narrow, academic learning - and more opportunity to learn in the workplace, to gain the skills and experience that employers demand."
Shadow Universities and Skills Secretary, David Willetts, said: "This is more evidence that young people are bearing the brunt of the recession.
"But this problem has been getting worse for more than ten years, long before the recession began. Now that times are harder, the problems are becoming more acute."