Aitken has spent the past three years as reserve driver for Williams, and made his first grand prix start in the 2020 Sakhir Grand Prix deputising for George Russell, who in turn replaced a COVID-19-struck Lewis Hamilton at Mercedes.
He maintained his relationship with the Grove-based squad even after ending his full-time single-seater career in 2021 in favour of a switch to endurance racing, but their agreement will not be renewed for 2023.
