Preventing lecturers from working beyond the age of 65 if they want to could lead to a staffing crisis in universities and colleges, according to the University and College Union.
As a legal challenge to the UK's compulsory retirement age by the charity Age Concern was referred to the European Court of Justice last week, the UCU said that it was crucial to allow people to work beyond 65. It said that 21.5 per cent of UK higher education teaching staff were aged 55-plus.
Some 37 per cent were aged 50-plus.
In further education, per cent of teaching staff - nearly 34,000 lecturers - were aged between 50 and 59, the union said. Some 19 per cent were aged under 35.
Current UK law permits employers to force staff to retire on their 65th birthday despite new age discrimination legislation. In the High Court last week, Age Concern claimed that the UK was not correctly applying new European Union legislation on the setting of the retirement age.
Roger Kline, head of equality and employment rights at the UCU, said: "I hope the European Court will rule in favour of the right to work beyond 65 if desired. Mature employees provide valuable experience and knowledge and skills that are not easily replaced."