TMW Unlimited has handled the account for eight years and will be repitching for the account.
The review is understood to be procurement-led. Infiniti expects the process to run until March with a new contract beginning in April next year.
A spokesman said: "It is a normal and healthy business practice at Infiniti to review its agency business from time to time.
"Infiniti has and will continue to have a very good working relationship with TMW Unlimited. They are fully aware of the situation and are certainly not excluded from applying for this new contract."