Greencore Group pushed ahead with its US expansion this week, acquiring Massachusetts-based ­sandwich maker On a Roll for an undisclosed sum.

On a Roll, which had gross assets of $3.4m as of 30 September, would provide an additional revenue stream to the group's US food-to-go category, would complement its businesses in Newburyport and Cincinnati, said group development director Eoin Tonge. "It is a promising, growing business with a well-diversified customer base of major retailers and c-stores," he said.

In November, Greencore reported an 18% uplift in sales for its US convenience foods business for the year to 24 September on the back of strong food to go volumes. It has attained top market position in fresh sandwiches and leaf salads in North Eastern US.

Meanwhile, Ranjit Singh Boparan, owner of chicken processor 2 Sisters Food Group, could be planning a move on Northern Foods, which last month announced a proposed merger with Greencore to create a business called Essenta. Speculation has mounted in the City that Boparan could propose a counter offer after building up a 6.6% stake in Northern Foods over the past few weeks.