Brasmlia: Brazilian President Michel Temer tried to defuse demands for his resignation on Saturday by claiming that the central piece of evidence against him in a corruption probe had been tampered with.

The dramatic claim came during what was only the second public appearance by Temer since the release on Wednesday of a secret recording in which he can allegedly be heard giving the green light to paying hush money to a jailed politician.

Calling journalists to the presidential palace in Brasilia, the centre-right president demanded the Supreme Court suspend its probe into alleged obstruction of justice and again vowed not to resign.

The high court said it would rule on Temer’s request of the investigation on Wednesday.

Temer said the secretly recorded audio had been “manipulated and doctored”, a charge that Brazil’s prosecutor general quickly denied.

The president also appealed to the Brazilian elite, saying that his leadership is needed to see through austerity reforms aimed at fixing Latin America’s biggest economy.

“I will continue to lead the government,” Temer said, touting signs that Brazil is finally inching out of its worst recession in history.

Prosecutor General Rodrigo Janot has accused Temer of attempting to block a huge anti-corruption investigation known as “Car Wash”.

The “Car Wash” investigation has upended Brazil with scores of politicians indicted or subject to probes into alleged bribe taking and embezzlement. Temer is only the latest to be pulled into the maelstrom.

At the heart of his scandal is a conversation he had with an executive from the JBS meat packing business, in which the president allegedly blesses monthly payments of hush money to jailed former lower house speaker Eduardo Cunha.

Cunha is in prison after a “Car Wash” judge convicted him of bribe-taking, but as a powerful insider he has long been rumoured to be threatening to spill secrets on other politicians.

Temer’s attack on the integrity of that recording — which is often hard to hear — appeared to be part of a carefully planned counter-attack after two days of near silence from the government.

Janot fired back a few hours later, saying that the recording had been tested and found to be “audible, intelligible and presenting a logical and coherent sequence.”

The chief prosecutor said he had nothing against further tests, but the Supreme Court should not suspend the investigation, since the probe “exists precisely to uncover the facts and to produce evidence.”

As long as Temer can keep his ruling alliance together — centred on his centre-right PMDB (Partido do Movimento Democrático Brasileiro) party and the PSDB social democrats — he can weather calls for his impeachment.

So far, major parties appear to be sitting on the fence, showing little overt support but not pulling out, either. A smaller party, the PSB, with one minister in the government, did quit on Saturday.

“At the top of our list is the immediate resignation of the president,” Julio Delgado, a PSB deputy, told journalists.

On Sunday, the crucial PSDB party leadership will meet, a spokesman said. There was no indication whether the meeting at around 2000 GMT would result in the party taking a position on its future in the coalition.

Sao Paulo Mayor Joao Doria, a rising star of the PSDB and seen by many as a strong candidate for president in scheduled 2018 elections, told Folha newspaper Saturday that there must be “good sense, balance, calm.”

In comments seen as backing Temer, Doria said the austerity reforms are the priority. “The reforms have to survive,” he said.

On Sunday, nationwide protests are planned by leftist groups and turnout will be closely watched as a gauge of the public mood.

Temer’s crisis comes barely a year after he took over in controversial circumstances after the impeachment of leftist president Dilma Rousseff for illegally manipulating the government’s accounts.

He was her vice-president in an uneasy coalition between his PMDB and her Workers’ Party, and took over automatically to serve out the rest of her term through 2018. Since then, Temer has radically changed the country’s previously leftist path, bringing in market-friendly reforms.

If Temer had to leave office, Congress would pick a replacement to rule until the 2018 elections.

However, there is widespread demand among Brazilians for advancing the 2018 polls and holding an immediate popular election. This would require Congress to approve a constitutional amendment.

The latest to demand snap elections was former leftist president Luiz Inacio Lula da Silva on Saturday. “We want Temer to leave but we don’t want an indirectly elected president,” he told supporters in Sao Paulo.