The new Italian eaterie opens on Monday (7 November) on the former site of fish restaurant Madame Prunier. It will be named Luciano after White's eldest son.
Forte and White are equal shareholders in the business. A spokeswoman for Forte said the deal was a "one-off" and he had no plans to get involved in other restaurant projects.
Luciano's 1930s interiors have been created by designer David Collins and will be divided into a 70-seat Johnnie Walker-sponsored bar and 135-seat restaurant. Average spend including wine is expected to be about £45.
"I'm moving back to my Italian roots," White said. "French food is too rich to eat every day of the week, but you can eat Italian every day and never get bored."
Both head chef Marco Corsica and general manager George Perende, were formerly at Conran restaurant Sartoria.
White and Forte worked together in the early 1990s when White operated an eponymous restaurant at the then Forte Hyde Park Hotel, now the Mandarin Oriental.
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