Students who are struggling with literacy and numeracy should not be able to go to university, a major international report suggests.
A traditional three-year degree course is costly and unsuitable for those who have difficulty with the basics, while having students graduate with low skills in these key areas "undermines the currency" of the qualification, according to the Organisation for Economic Co-operation and Development (OECD).
The study, which looks at literacy and numeracy skills in England, concludes that 7% of 20 to 34-year-old graduates in England have numeracy skills below level two, while 3.4% have literacy skills below this level - meaning that they struggle to estimate how much petrol is left in a tank from looking at the gauge, or have difficulty understanding instructions on an aspirin bottle.
For numeracy, this is worse than in other nations - including Australia, Ireland, Poland, Italy and Spain, the report shows.
Around one in five young university graduates can manage basic tasks, but struggle with more complex problems, it adds.
"Those with low basic skills should not normally enter three-year undergraduate programmes, which are both costly and unsuited to the educational needs of those involved, while graduates with poor basic skills undermine the currency of an English university degree."
These would-be students should be encouraged to take alternative, professional courses that will help to boost their levels of literacy and numeracy, while more needs to be done in universities to help students with intermediate levels in the basics to develop their skills.
It also suggests that preventing universities from graduating students that have low basic skills could help to raise achievement.
The report, based on an international survey conducted in 2012, goes on to warn that while England has more young people graduating from university than many other countries, many young people are not well-prepared for degree study as the basic skills of those teenagers who may go into higher education is much weaker than elsewhere.
Overall, a third of 16 to 19-year-olds are struggling with the basics - three times as many as in countries such as Finland, Japan, Korea and the Netherlands.
In 2012, in England, 70% of youngsters in this age group were in education or training that would lead to a formal qualification, compared to almost all young people in many other nations, the survey says.
The OECD warns: "In England, the weak basic skills of young adults compared with other countries can be traced back to a lower standard of performance at the end of initial education."
"The priority of priorities is to improve the standard of basic schooling in England," it adds.
The report notes that a raft of reforms have been introduced, including an overhaul of qualifications, raising the age that youngsters must stay in education or training to 18 and a decision that any teenager who does not gain at least a C at GCSE in English or maths must continue with the subject.
It is too early to assess the impact of these reforms, the OECD says, but adds that "their objectives are clearly the right ones".
The organisation does note that the move to lift the cap on university numbers could worsen the problem of students with low basic skills.
Overall, there are an estimated nine million working-age adults in England with literacy or numeracy skills, or both, the report says.
A Government spokeswoman said: " Good English and maths skills are essential to success in later life, and thanks to our reforms thousands more students are leaving education with these vital skills.
"While we are pleased the OECD recognises the progress we have made, we are not complacent, and will maintain our relentless focus on literacy and numeracy so all young people have the chance to succeed."
Mike Ellicock, chief executive of National Numeracy, said: "There is a big gap between the maths young people learn at school - in effect complex maths in simple situations - and the maths all of us need every day - simple maths in complex real-life situations.
"We need a new approach to bridge that gap and to help adults build the skills they never truly learnt at school."