The top three floors of the building are home to a private members' club, restaurant and bar, with event space and private dining rooms to hire.
As part of a new push into the prestige catering market, Ferns will also provide a selection of machines for Searcys, including traditional espresso systems, automatic bean-to-cup and filter coffee machines, as well as ongoing maintenance support.
Coffee will now include both Ferns' Costa Rican filter coffee blends and Sassetta, a brand new artisan blend for coffee aficionados.
Managing director Martin Sheridan said: "We're delighted to be working with such a prestigious venue, which marks the start of an exciting new direction for Ferns Coffee."
By Lisa Jenkins
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