The Brazilian subsidiary of US retail giant Wal-Mart Stores is expected to announce a deal to purchase the local supermarkets of Portuguese retailer Sonae by the end of November, according to a report in local newspaper Folha de S.Paulo quoted by the the Dow Jones news agency.

According to the report, a deal has been reached but the two sides are still hammering out final details. Previous market estimates had pegged the value of the deal at $700 million.

Wal-Mart increased its presence in Brazil last year with its $300 million purchase of the Bompreco supermarket chain. The deal netted Wal-Mart 120 stores in northeast Brazil.

 A purchase of Sonae, which is Brazil’s fourth-largest supermarket chain with 148 stores, would put the heat on rival retail chains Companhia Brasileira de Distribuicao  or CBD, and France’s Carrefour. CBD and Carrefour are the top two retailers.