Roark Capital, a US private equity firm focused on leveraged buyout investments in the franchise/multi-location, restaurant and food, health and wellness, and business services sectors, is closing in on a $9.6bn deal to acquire sandwich chain Subway, according to a report by the Wall Street Journal.

The report cites unnamed sources familiar with the matter as revealing that Roark, which has around $32bn in assets under management, could finalise a deal as early as this week.

The firm already owns restaurant chains Arby's and Buffalo Wild Wings, as well as Baskin-Robbins and Dunkin' via its investment in Inspire Brands.

A previous report by Reuters earlier this month revealed that private equity firms TDR Capital and Sycamore Partners were in talks over a joint bid to acquire Subway, after the family-owned firm said in February it was exploring a possible sale of the business.