Wagamama, the fast casual noodle chain, has told how it believes there is scope for 650 managed sites in the US.

Speaking at M&C Report’s Restaurant Conference yesterday, Steve Hill, its chief executive, said they had refined its restaurants in the States following a huge amount of customer feedback in a bid to achieve its ambitions.

They now feature an expanded colour scheme, seating booths, subdued lighting and TV screens and Hill said that as a result of the changes its site in Prudential, Boston, had seen a 15% increase in sales.

The company has also appointed a US chief operating officer and a head of marketing in an attempt to break into the heavily branded restaurant market.

He told delegates at Plaisterers’ Hall in the City that Wagamama was expanding using a “hub and spoke” plan and that it had opened in Boston first because it had wanted to make changes to its US offer “under the radar” before rolling out.

The group plans on expanding mainly on the East Coast at first and said that Boston alone could cater for 40 restaurants.

However, unlike other areas globally Hill said the lion’s share of its sites would remain company owned in the US.

The chief executive remained tight-lipped over potential bidders for the restaurant chain, other than saying its owners Lion Capital had decided that now was the right time to sell.

Earlier this week reports suggested that India Hospitality Corporation (IHC), the Aim-listed Indian leisure group, was leading the charge in the takeover battle for the group.

It is understood to be one of three bidders still in the hunt for Wagamama, alongside Morgan Stanley’s private equity arm and InvestCorp, the Middle Eastern buyout group.

IHC, which raised £64m when it floated on AIM in 2006, owns Sky Gourmet Catering, an airline caterer with 1,700 employees. Since 2007 it has owned Gordon House Hotels and Mars Restaurants, a multi-brand operator with concepts including China Joe, All Stir Fry, Birdy’s Bakery and Patisserie and Tendulkar’s.

There are rumours that it could use its bid for Wagamama as a springboard to move its listing to Nasdaq as well as to develop the brand across India.