The move comes as K10, founded 12 years ago by Chris Kemper, acquires the former Ping Pong site in Broadgate, London with a view to converting it into a K10 restaurant early next year.
Kemper, who was recently joined in the business by restaurant consultant Maurice Abboudi, takes £40k on average per week at the 70-cover Copthall Avenue restaurant by serving sushi, sashimi and selected hot dishes to city workers and is keen to take the concept further.
Investment for expansion
Neill, who left Wagamama last year, will take a 'significant stake' in the restaurant and become chairman of the board following his investment. Chris Kay of Chrysalis VCT will also join the board.
The former Wagamama boss is well-placed in helping to build K10. In his 13-year tenure at Wagamama he increased its number of UK sites from two to 65.
Neill said it had been difficult to find a reason not to invest in the conveyor-belt restaurant K10, which has an average customer turnaround of 30 minutes.
"I was absolutely knocked out by the food quality and value at K10. The lines of happy customers demonstrated I wasn't the only one who appreciated what Chris, Maurice and the K10 team have achieved," he said.
The company plans to add another two restaurants to its estate by 2015 following the opening of its second site in Appold Street, Broadgate next year. Sites are reportedly already being considered for the company's expansion with a third expected to be announced imminently.
Abboudi said the investment was key to expansion. "Chris Kemper and I are delighted that K10 has secured new investment from backers as experienced as Chris Kay and Ian Neill. Their contribution to the board will be significant in the development and expansion of K10," he said.