Shares in Carrefour moved higher today after the French supermarket retailer said it would buy Grupo BIG in a deal that values Brazil's third-biggest food retailer at about $1.3 billion.

The deal is the first significant acquisition by the French food retailer since a possible takeover by Canada's Couche-Tard unravelled in January after opposition from the French government. 

Carrefour, Europe's largest retailer, said last month it was "highly confident" it could accelerate its turnaround on its own and that smaller bolt-on acquisitions could help to spur growth. 

Carrefour will buy BIG, which operates 387 stores and generated sales of 24.9 billion reals ($4.51 billion) in 2020, from Walmart and investment firm Advent International. 

"We view the move as bold and proof that Carrefour is on the front foot in its core markets," JP Morgan said in a note. 

"Our group is on the offensive," Carrefour chairman and chief executive Alexandre Bompard said in a statement. 

Carrefour already has a major presence in Brazil, where its subsidiary Carrefour Brasil is the country's biggest retailer by most measures and runs the Atacadão supermarket stores. 

In France, where rivals include Casino and Leclerc, Bompard has made reviving flagging sales at hypermarket stores a priority. 

A successful acquisition would make Carrefour the uncontested market leader in Brazil and create a new strand of earnings growth above and beyond French margin expansion. 

The group said the transaction valued Grupo BIG at an enterprise value of 7 billion reals ($1.3 billion). 

The acquisition will be made 70% in cash and 30% through newly issued Carrefour Brazil shares. After completion, Carrefour Group will own about 67.7% of Carrefour Brazil compared to the current 71.6%.