The news came as Legal & General Property signed-up Cineworld for a nine-screen cinema within the new development which is due to open in early 2018.
Work on the £85m retail and leisure extension is due to start on site in late 2015 and includes 175,000 sq ft of new retail space.
Simon Russian, Head of Retail Development at Legal & General Property, said: “The accessibility of the Arndale Centre to all modes of transport is a key factor and this major letting to Cineworld will act as a catalyst to boosting the Town’s evening economy, bringing with it a wide range of quality, family based restaurants.
“This is a significant step forward in the re-positioning of one of the South Coasts most successful shopping centres.”
The existing scheme is anchored by Marks & Spencer, BHS, Sainsbury’s, River Island and Primark, whilst earlier this year H&M announced that it has taken a 23,000 sq ft pre-let on the extension, acting as its first anchor.