RIO DE JANEIRO -- Embattled Brazilian President Michel Temer says he will only leave office if forced out because stepping down would be an admission of guilt in a corruption scandal that has led to growing calls for his ouster.

In an interview published Monday in the Folha de S.Paulo newspaper, Temer said he is innocent and will remain in office with the help of his shaken congressional base until December 2018 so he can go forward with austerity measures and unpopular reforms.

"I will not resign. If they want, force me out, because if I resign that will be a declaration of guilt," Temer said.

Also on Monday, ex-President Luiz Inacio Lula da Silva was charged for the third time by prosecutors before judge Sergio Moro. Prosecutors say they believe Silva committed crimes of corruption and money laundering because of his frequent use of a farmhouse outside Sao Paulo. It is now up to Moro, who is hailed by many as an anti-corruption hero in Brazil, to decide whether the former president will stand trial in the case.

Silva denies any wrongdoing and said the farmhouse belonged to one his friends.

With respect to Brazil's current president, the supreme court has opened investigations into Temer for allegedly obstructing justice, passive corruption and being a member of a criminal organization. The move follows release of an audiotape that appears to show him endorsing the payment of hush money to an imprisoned former ally in exchange for silence.

Businessman Joesley Batista, who made the recording, also said in plea bargain testimony that he paid Temer and his allies millions in bribes and illegal campaign funds.

Temer has also been accused of negligence for failure to take any measures after hearing Batista say he was paying bribes to two judges and a prosecutor. The meeting with Batista, the owner of giant meatpacker JBS, took place in March.

In the interview, Temer also said he was "naive to welcome a person (like Batista)" at the vice-presidential palace in the middle of the night without any prior information published in his official schedule. The business mogul was already under three legal investigations at the time.

The pressure on Temer increased over the weekend with some allied parties leaving his base in Congress and Brazil's prestigious bar association deciding to push for the president's impeachment. Small protests happened in 19 cities nationwide against the embattled leader, whose popularity is currently at 9 per cent, according with a recent Datafolha institute poll.

As a result, consultancy Eurasia increased from 20 to 70 per cent the chances that Temer will not finish his term.

Later on Monday, Brazil's top court decided to wait for Batista to hand over to federal police the equipment used to record the president and the original audio obtained from their conversation.

Temer's lawyers welcomed the court's decision to audit the material, which gives more the president more time to organize his defence.

The president insists the tapes should be audited before the investigations proceed. A forensics expert hired by Temer said in a press conference that the recording has "70 moments of obscurity" and called it "useless" as evidence.

Claudio Lamachia, the head of Brazil's bar association, kept the pressure on the president, though, criticizing Temer for welcoming Batista to the palace in the middle of the night and promising to push for his impeachment regardless of the audios.

The bar association will give to Lower House Speaker Rodrigo Maia later this week its first request for Temer's impeachment. There are already eight requests on Maia's table.