If a contract of employment is terminated by mutual consent, is an employee still entitled to claim unfair dismissal?

When a contract of employment is terminated by mutual consent or by agreement between employer and employee, in theory the employee has no entitlement to claim unfair dismissal. However, if the facts surrounding the termination indicate that pressure was brought to bear by the employer on the employee to resign, it could be held that the employee was in fact dismissed. A court or tribunal would also need to establish whether there was an equality of bargaining position between the parties or if any offer was presented on a take it or leave it basis and used as a method to force an employee to "resign".