The development bank had already expressed the intention to sell its stake "for the right price". But the person, who asked for anonymity to discuss the bank's strategy freely, denied any ongoing negotiations to sell the 20 percent stake.

Veja magazine reported earlier on Friday that JBS' controlling shareholder Joesley Batista was negotiating a potential sale of the stake held by the bank to a Qatari sovereign wealth fund. The source with knowledge of the bank's strategy denied the talks.

BNDES declined to comment on the matter. JBS shares closed up 3.14 percent on Friday, reducing this year's losses to 6 percent.