The document is in the "final stage of completion" and will be forwarded next week to the court responsible for Americanas' bankruptcy protection process, which the retailer entered shortly after it unveiled in January "accounting inconsistencies" of at least 20 billion reais ($3.81 billion).

"The final report will be closed and read on Monday before being presented to the court," said the source.

Americanas declined to immediately comment.

Since January, more than 100 accounting, finance and legal experts on staff at Americanas' court-appointed trustee have been working on the retailer's accounts to identify reasons for the inconsistencies.

Americanas, backed by the billionaire trio that founded investment firm 3G Capital, has accumulated debt of more than 40 billion reais.

After the document is submitted, the court will set a deadline for Americanas to present its judicial recovery plan.

On Thursday, Americanas' former chief executive testified at Brazil's securities watchdog, according to a source.

($1 = 5.2515 reais)

(Reporting by Rodrigo Viga Gaier; Editing by Richard Chang)

By Rodrigo, Viga and Gaier