U.S.-based private equity firms Warburg Pincus and EIG Global Energy have placed bids for shallow water mature oil fields being sold by Brazil’s state-controlled oil, gas, and energy producer Petroleo Brasileiro S.A. (Petrobras), as the private equity firms seek to carve out a presence in Latin America’s top oil producer.

The clusters located in the Campos basin off the coast of Rio de Janeiro state are likely to fetch proposals of around $1 billion in total, which would help boost a wider effort by Petrobras to sell assets and reduce debt.

Goldman Sachs will also provide debt financing for the bid, Trident Energy, a Warburg Pincus-backed firm specializing in mid-life oil assets, also bid for the clusters.

A win by either group would represent those private equity firms’ debut in the oil production business in Brazil.