Restaurateur Alan Yau has teamed up with private equity firm Phoenix Equity Partners to develop the Busaba Eathai concept into a chain.

The joint venture will see £21.5m being invested in 20 to 30 new sites across the UK over the next five years.

Busaba is Yau's Thai dining concept. The first Busaba site opened on Wardour Street in London in 1999. There are currently three Busaba's, all in the capital.

Yau, who found the famous Japanese restaurant Hakkasan as well as the Wagamama chain, said: "I'm delighted to be working with a partner who has helped build so many superb brands and look forward to introducing our very different approach to restaurant dining to many areas of the UK."

Stephen Gee, currently the chair of Gaucho Group, will become chair of the newly formed Busaba Group.

David Burns, partner at Phoenix, added: "Investing in Busaba at such an exciting stage in its development, is a great opportunity for us. We see huge potential in building this exciting new brand in the UK restaurant sector."