Amazon has joined forces with Morrisons to offer "hundreds" of Morrisons products through its food delivery service Amazon Pantry and its subscriber service Amazon Prime Now.
The deal will give Amazon customers access to Morrisons' fresh and frozen products, the supermarket said.
Morrisons chief executive David Potts said the combination of the supermarket's "fresh food expertise and Amazon's online and logistics capabilities is compelling".
He added: "This is a low-risk and capital-light wholesale supply arrangement that demonstrates the opportunity we have to become a broader business."
The announcement comes after supermarket Sainsbury's upped the ante in the highly-competitive grocery sector last month when it tabled a £1.3 billion bid for Argos-owner Home Retail Group in an attempt to become a ''world-leading'' retailer bigger than John Lewis and Amazon UK.
But the proposed deal faces competition, with South African-based furniture retailer Steinhoff making a rival offer for Home Retail Group at £1.4 billion.
Amazon heaped more pressure on the British grocery market in November last year when it launched a grocery service for Amazon Prime members with thousands of products.
Amazon Pantry delivers groceries and household products to subscribers for a fee of £2.99 per box.
Meanwhile, Morrisons also said it was pressing ahead with plans to bolster its website after agreeing a deal in principle with online grocery retailer Ocado. It said it would take up space at Ocado's new customer fulfilment centre in Erith, south east London, in a move to "sell to customers all over Great Britain".
It comes after the grocer signed a £170 million contract with Ocado in 2013, providing it with its first online delivery service.