Employers cannot require employees to retire at a certain age, unless this can be objectively justified. However, employees can still choose to retire from employment by giving notice under their contract.
When discussing retirement plans with an employee, to avoid the risk of a claim of age discrimination, the employer should be cautious not to give the impression that the employee is expected to retire at a particular time.
If an employee indicates that they wish to retire, it will be appropriate for the employer to discuss relevant issues, such as the possibility of a phased retirement and the handover to a successor.