Asda has completed a deal worth around £600m to buy the Co-op's petrol forecourt business.
The supermarket, which is owned by the billionaire Issa brothers and TDR Capital, said 2,300 workers will move over from the Co-op to the group.
The new focus in forecourts and convenience stores comes after Asda's £6.8bn takeover by the billionaire brothers and their private equity backer, who also own the EG Group forecourt giant.