Westfield chiefs have confirmed that John Lewis has signed-up for a 230,000 sq ft store in the planned extension.
The four-storey store will cost around £30m and be one of the biggest department stores in the country.
Westfield’s giant regeneration scheme will be phased over more than 15 years and includes plans for up to 1,500 homes in five high-rise blocks, ranging from eight to 20 storeys.
The plans include a new public green, offices and an extension of the existing shopping centre in Wood Lane with new restaurants and a leisure complex.
Westfield will also contribute £20m toward community improvements, including £3.9m for works at Shepherds Bush overground train station and £1m towards highways and junctions.