The two firms signed a memorandum of understanding to allow Gol to acquire 100 percent of WebJet capital stock, pending regulatory approval.
With the deal, Gol would increase its market share of the domestic Brazilian market from 36 percent to 41 percent.
Gol, created in 2001, operates some 900 daily flights to 59 cities in Brazil and 14 international destinations in South America and the Caribbean.
WebJet serves 16 domestic locations with around 1,000 flights per week.
The deal comes as regulators are considering a plan by the largest Brazilian airline, TAM, to merge with Chile's LAN to create the largest Latin American carrier.
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