Fitch Ratings on May 21 placed BRB-Banco de Brasília SA's long- and short-term issuer default ratings of BB- and B on rating watch negative.

Aside from the bank's IDRs, the bank's long- and short-term national ratings of A+(bra) and F1(bra) and the viability rating of "bb-" were similarly placed on negative watch.

In placing the ratings on watch negative, Fitch explained BRB has not yet published audited financial statements for year-end 2018. The rating agency said the delay limits Fitch's full assessment of the bank's financial metrics and overall credit profile.

The negative watch also reflects uncertainties caused by an ongoing audit of the bank by accounting firm PricewaterhouseCoopers LLP since April, aimed at probing possible irregularities in BRB's legal, financial, procedural and information systems over the last six years.

Fitch said it will resolve BRB's negative watch status once it publishes its audited financial statements for year-end 2018.

The rating agency also warned the bank's viability rating may suffer a downgrade if the bank's credit profile diminishes, or if irregularities are found in the audit. The downgrade on the viability rating may also drive a cut in the IDRs and national ratings.