The company, which has managed both sites for five years, has purchased them from landlord Covent Garden London for an undisclosed sum.
Both Tuttons and Dirty Martini will close shortly to undergo a refurbishment programme overseen by Russell Sage Studios, whose other projects have included the Savoy Grill and Pétrus for Gordon Ramsay Holdings, as well as Balcon and the Zetter Townhouse.
Hugh Fowler, managing director of CG Restaurants, said buying Tuttons was a "hugely exciting" step for the group. "It has an exceptional reputation and a loyal clientele of locals and visitors who seek it out for quality food and great service, which makes it an enticing business opportunity," he said.
"As Covent Garden London continues its excellent work to enhance the area, we have exciting plans to transform Tuttons in the coming months to help us appeal to the changing demographics of the Covent Garden visitor."
Sarah-Jane Curtis, director of Covent Garden London, added: "We are looking forward to the relaunch of both Tuttons and Dirty Martini following the redesign by Russell Sage Studios. The investment in both businesses by CG Restaurants is fantastic news for the neighbourhood."
By Kerstin Kühn
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