Walmart has offered 62 rand for each outstanding Massmart share, which represents a premium of 53% to Friday's closing share price, Massmart added.
Since acquiring majority control over Massmart in 2010, the U.S. retailer has had to provide increasing levels of financial and operational support across Massmart's businesses.
Massmart's management launched a turnaround plan in 2019 that involved selling off non-core assets, removing fresh food from its Game stores and cutting costs across the group.
But issues such as the COVID-19 pandemic and the civil unrest in 2021 had held up the turnaround plan, Massmart said.
"The potential offer, if finalised, will provide Massmart with needed access to ongoing financial and operational support from Walmart to sustain the group's turnaround," it added.
Massmart Chairman Kuseni Dlamini told reporters in a call that a preliminary report from an independent expert indicates that the terms and conditions of the offer are fair and reasonable.
The retailer posted a headline loss in the 26 weeks ended June 26 of 903.5 million rand ($53.2 million), from a loss of 358.5 million rand a year before.