University graduates face "significantly reduced" job prospects this summer, according to a poll of Britain's top 100 companies, which shows there are a third fewer graduate vacancies than last year.
Almost all of the top employers have already filled their 2009 vacancies or have stopped accepting applications, and job opportunities have been cut in nearly all sectors.
The findings confirm widespread fears that this summer's university leavers face the toughest competition for jobs in decades.
A recent Guardian survey revealed that up to 40,000 graduates face unemployment on leaving university this summer.
High Fliers Research, an independent market research company specialising in graduate recruitment, polled 100 household-name recruiters including Barclays, Marks and Spencer, Oxfam and Rolls-Royce.
Vacancies for this summer's graduates have been cut by 28% since last year, and almost two-thirds of employers have reduced their graduate recruitment targets – of which half have cut at least 50 places from their graduate schemes.
Of the 20,000 graduates that top employers planned to recruit in 2009, vacancies for 5,500 have been cancelled or left unfilled, and 13.5% fewer graduates will start work with the UK's leading employers this year than in 2008.
Jobs have been cut in almost all sectors, with the City worst hit – there are 56% fewer entry-level jobs in investment banking this year.
Vacancies in accountancy have been cut by 22.5%. But it remains the biggest graduate recruiter, taking on 3,253 graduates this year, the most of any sector, and with relatively few applications per graduate training place: 15, compared with an average of 45.
Vacancies in IT and telecommunications have dropped 51%, and those for engineering and industrial jobs have fallen 41%.
The only sectors looking to take on more graduates this year are the armed forces – which are recruiting 11% more graduates this year – retailing, and the public sector.
Employers are receiving an average of 45 applications per graduate vacancy, a third more than in 2008.
However, two-thirds of employers expect to maintain or expand their graduate recruitment in 2010.
Martin Birchall, managing director of High Fliers Research, said: "With a record number of students graduating from UK universities this summer, these substantial cuts in graduate recruitment at Britain's best known and most sought-after employers couldn't have come at a worse time.
"The class of 2009 is facing one of the toughest job markets of the last two decades, and there is now the very real prospect that tens of thousands of new graduates will be left unemployed after leaving university this year."
The higher education minister, David Lammy, said: "These are undoubtedly tough times, but a degree is a strong investment, which stands graduates in good stead for a long and successful career.
"Like everyone in a recession, it is natural for some students to feel concerned about their futures, which is why we are working hard to show that real opportunities are available to them, including getting into work, finding an internship, entering further study and volunteering.
"Research shows that jobs are available and that in some areas there has been growth – but for those students who have not yet found work, we have introduced the 'graduate talent pool', produced additional advice and will shortly make available up to 45,000 professional and career development loans for further study by 2010."
Wes Streeting, president of the National Union of Students, said: "Given the high levels of debt currently being accrued by students because of fees, this news will be extremely worrying for this year's graduates.
"And it isn't just graduate jobs which are at risk. Many students have to work part-time to finance their studies, and we may see more of them having to drop out if they lose these jobs."