Mandatory retirement ages can often be a counterproductive means of restructuring a senior workforce, it has been claimed.

While the European Court of Justice has just this week ruled that businesses are not acting against EU law by requiring workers to leave once they reach the age of 65, intelligence chiefs have claimed that staff retention is often the best means to success.

According to MI6 head John Scarlett, the knowledge and skills possessed by senior workers can often be a huge advantage to an organisation.

Newly-released papers reveal that the spy chief told a parliamentary committee: "We need their experience … having retirement age as your major mechanism for moving people in and out of senior levels is not a good ideal."

Also opposed to mandatory retirement at the age of 65 is Age Concern, with the charity having argued that the current legislation represents age discrimination.

The charity, which brought the case to the European Courts, has vowed to carry on its flight to end the practice.