Tesco has said it is planning a "long-term, strategic alliance" with French supermarket chain Carrefour, as the retail giants try to cut costs in the face of increasing competition.
The two said their alliance would "cover the strategic relationship with global suppliers" and the "joint purchasing of own-brand products".
They said this would improve "the quality and choice" of goods available.
It would also enable them to cut prices, the statement said.
Tesco chief executive Dave Lewis said: "By working together and making the most of our collective product expertise and sourcing capability, we will be able to serve our customers even better, further improving choice, quality and value."