High-profile chef Theo Randall has taken an unspecified minority stake in the Azzurri Group, which owns the ASK Italian and Zizzi restaurant chains, according to The Times.

As a result of his stake, the chef, who has already been working with ASK on its menus, product- sourcing and training, has expanded his involvement in product-sourcing to Zizzi, although he is not involved with its menus.

Steve Holmes, the chief executive of Azzurri Group, the new holding company for ASK and Zizzi, told the newspaper that like-for-like sales in both were growing strongly and that the business had returned to the acquisition trail.

Azzurri Group has about 112 ASK outlets and 136 Zizzi restaurants.

Talking earlier this year, Holmes told M&C Report that he believed there is huge potential for both brands and that the Bridgepoint-backed business has not ruled anything out with regards to further acquisitions or international expansion but that its focus at the moment is on its UK rollout.

Holmes told The Times there was an opportunity to expand the number of outlets of both brands to about 250 each in the UK, while a site in Ireland was possible.

Last month, Azzurri retained Lunson Mitchenall to support its expansion in the south east, with plans to add 20 restaurants in the next year.