BRASILIA (Reuters) - Right-wing President-elect Jair Bolsonaro vowed in a tweet on Thursday to investigate Brazil’s state-run national development bank, BNDES, for corruption by opening its “black box” of secret transactions.

Brazil's President-elect Jair Bolsonaro talks to the media, in Brasilia, Brazil November 7, 2018. REUTERS/Adriano Machado

The BNDES is the largest development lender in the Americas with a loan book larger than the World Bank’s. Under the leftist Workers Party governments in recent years it financed projects in many Latin American and African countries.

Bolsonaro, a former Army captain turned nationalist politician who takes office on Jan. 1, criticized the BNDES during the election campaign for funding projects that had nothing to do with Brazil’s national interests, such as the container terminal at communist-run Cuba’s port of Mariel.

“I will begin my mandate determined to open the black box of the BNDES and reveal to the Brazilian people what was done with their money,” he said in Thursday’s tweet.

In 2011, the BNDES disbursed in Brazil, Latin America and Africa funds totaling $83 billion, more than the World Bank, the Inter-American Development Bank and the International Monetary Fund put together. Lending dropped off due to Brazil’s deep 2015-2016 economic recession and a graft investigation into the county’s top engineering and construction conglomerates that were among the banks main private borrowers.

The bank declined to comment on Bolsonaro’s vow to probe its lending transactions.

The BNDES’ employees association said in a statement that the bank published ample information about its operations on its website and followed the law regarding bank secrecy.

The bank reports its accounts regularly to Brazil’s securities and exchange commission and the controller general and federal accounts court, besides being the target of three congressional inquiries that did not find any irregularities, the association said.

“Until today, there has been no evidence that could link BNDES employees to any corruption scheme,” it said.

A BNDES official told Reuters that the bank’s operations where open and transparent and had nothing to hide.

“The bank has no black box. Nobody here fears anything and nobody feels threatened or guilty,” the source said, requesting anonymity because he was not authorized to speak about the matter.

In 2016, BNDES temporarily froze disbursements worth $4.7 billion for several engineering firms ensnared in Brazil’s biggest corruption investigation, the Car Wash probe into overpriced contracts with oil company Petróleo Brasileiro SA. The suspension affected projects in Argentina, Cuba, Venezuela, Guatemala, Honduras, the Dominican Republic, Angola, Mozambique and Ghana.