The agreement follows a Memorandum of Understanding announced in February.
The extension includes the creation of a joint venture to provide logistics services to Ocado-powered customer fulfilment centres in France, which will be available to all grocery retailers.
Groupe Casino will also use Ocado’s in-store fulfilment technology in its Monoprix stores.
Ocado will integrate Octopia’s marketplace platform into its Ocado Smart Platform (OSP), and allow OSP partners around the world to launch their own marketplace offerings.
Octopia is a subsidiary of Cdiscount, which is fully controlled by Cnova, the e-commerce arm of Casino.
Ocado agreed its first deal with Casino in 2017.(Reporting by James Davey; editing by Kate Holton and Jason Neely)