The deal will enable Wm Morrison to compete more aggressively in the home delivery space by giving it nationwide coverage.
The company is likely to announce the deal, to take capacity at an Ocado warehouse in Kent, in the coming days, Sky News reported.
Currently, Morrisons.com can service around half of UK households. The new arrangement, restructuring a 2013 deal between the firms, will widen its service across the UK.
The deal will also include Morrisons being provided with a store-picking service by Ocado.
The supermarket announced in February that it had reached an agreement in principle with Ocado to grow Morrisons.com.
The company said at the time that the deal would “only proceed if it enables Morrisons to achieve profitable growth online”.
Morrisons also announced in February that it had struck a new supply agreement with Amazon, making hundreds of its products available on the website.
Morrisons and Ocado declined to comment.