Petrobras has begun the non-binding phase of a sale of exploration, development and production rights for three sets of onshore fields, the state-controlled company said Nov. 17.

Potential buyers that qualified in a previous phase will have access to data on the Polos Riacho da Forquilha, Buracica and Miranga fields in the northeastern states of Bahia and Rio Grande do Norte.

The sale was announced in August and is part of plans by the world’s most indebted oil company to offload billions of dollars in assets to bolster a balance sheet that has been weakened by sinking oil prices, mismanagement and a graft scandal.