Adds details of Petrobras statement in paragraphs 2 and 7, further Ibama remarks in paragraphs 5 and 8, background in 4

RIO DE JANEIRO, May 19 (Reuters) - Brazilian environmental agency Ibama said on Monday it approved Petrobras' concept of an emergency plan to assist local fauna in case of an oil spill in the Foz do Amazonas basin, putting the firm closer to a license to drill in the area.

The move allows Petrobras PETR4.SA to conduct a simulation of its plan, and, according to the firm, is the last step before Ibama rules on a license for the company to drill off the northern Brazil coast.

Ibama denied Petrobras' request in 2023 for an offshore drilling license for the Foz do Amazonas, citing environmental concerns.

The Foz do Amazonas area harbors a massive system of coral reefs teaming with marine life.

The oil company appealed soon after, but a final Ibama decision is pending, creating tensions between the government agency and the state-run firm.

The upcoming simulation aims to verify the effectiveness of Petrobras' proposed emergency plan, Ibama said in a statement.

The aimed area, in the northernmost part of Brazil's Equatorial Margin, is considered Petrobras' most promising oil frontier, sharing geology with nearby Guyana, where Exxon Mobil XOM.N is developing huge fields.

"We are pleased to advance to this final stage and to be able to prove that we are able to operate safely on the coast of Amapa," Petrobras Chief Executive Magda Chambriard said in a statement.

Ibama said it will work out a schedule with Petrobras to carry out the simulation.

(Reporting by Fabio Teixeira in Rio de Janeiro and Andre Romani in Sao Paulo, Editing by Natalia Siniawski and Sandra Maler)

((Andre.Romani@thomsonreuters.com; 11 991314109;11 56447500;))