Last year Brian Arthur, 59, won a tribunal claim against Durham New College (DNC), which was ordered to pay the back-dated contributions.

Proceedings dragged on for 14 years and ended in an unexpected twist on Thursday when DNC was released from the payments by a loophole in European law.

Speaking after the tribunal, Mr Arthur said: "It is the difference of me being able to retire at 65 or going on until I am 70."

The music lecturer worked for Northumberland County Council from 1985, and left a year after employment was transferred to DNC in 1993.

Last year's tribunal assumed that under the Higher Education Act all terms of employment, including pensions, were passed to the new employer in the transfer.

But the loophole dictated that workers in the prison service have to claim for back-dated pension payments within six months of leaving their job.

Although Mr Arthur protested that the transfer to DNC took place in April 1993, the previous tribunal ruled on an agreed date of September 1993.

Mr Arthur missed the time frame to claim his owed pension contributions and was powerless to appeal.

Nicolas Garside, chairman of the tribunal, said: "If you had been working at Ashington Technical College, you would have been entitled to a pension because the Act provided for that, but people in the prison service are not brought under the Act."

He went on to explain that a similar ruling in the South Manchester High Court meant the tribunal was bound by precedent.

Mr Arthur, from Warkworth, Northumberland, said: "With all the time and money they have put into this, it would have been cheaper to pay up.

"I feel distressed about how long this has gone on for. It's affected my health. I had to go and see my GP because my blood pressure went through the roof."

Mr Arthur, who still works for Northumberland County Council, but in a different capacity, said he would consult his union, the National Association of Schoolmasters and Union of Women Teachers.