Online grocer Ocado is understood to have held talks with French retailer Carrefour about a partnership to deliver shopping to customers’ homes in France.

It is thought Carrefour executives visited Ocado’s warehouse in Hertfordshire recently to see the operation.

A joint venture would see Carrefour use Ocado’s software for online grocery deliveries, beginning in Paris.

A source told The Independent that Ocado’s staff had been “sworn to secrecy” about a possible partnership with Carrefour.

Founder Jason Gissing has said in the past that Ocado is seeking international expansion and had been approached by several interested partners.

The move comes as Ocado prepares for an IPO next year despite the fact it has yet to make a pre-tax profit.

Chief executive Tim Steiner and new financial director Andrew Bracey have been visiting investment banks ahead of a public stock offering.