Brazil's President Michel Temer on May 26 appointed the economist Paulo Rabello Castro as the new head of state-run development bank Banco Nacional de Desenvolvimento Econômico e Social, or BNDES, replacing Maria Silvia Bastos Marques, who resigned the same day citing personal reasons after a year on the job.

Castro, who heads the national statistics agency IBGE, will take over as the new chief of the state-run bank as early as this week, according to a statement from the president's office.

A government source familiar with the matter told Reuters that Marques' exit was not politically motivated. Still, her resignation comes amid increased turbulence at BNDES.

A federal investigation was recently launched into suspicious loan operations between BNDES and meatpacking firm JBS. The alleged collusion reportedly cost the federal government $380 million, and some of the funds were said to have been used as donations to political campaigns, including those of Temer and two of his predecessors, Dilma Rousseff and Luiz Inácio Lula da Silva.

The bank's staff had also threatened to go on strike if Marques did not publicly defend them following the lending allegations.