Temer said Monday that he was "naive" to hold the late-night meeting which sparked an explosive corruption scandal, but insisted he'd done nothing wrong and wouldn't resign.
Temer, who faces multiple impeachment demands, told Folha newspaper he had innocently stumbled into the crisis threatening to bring him down just over a year since he replaced impeached president Dilma Rousseff.
"Naivety. I was naive," he said.
The scandal erupted last week when Globo newspaper revealed a secret audio recording in which Joesley Batista, an executive from the JBS meatpacking giant, can allegedly be heard getting the president's green light for paying hush money to a politician imprisoned for corruption.
With Temer placed under investigation for obstruction of justice and corruption, opponents are demanding his head.
Impeachment petitions are piling up. The highest-profile request was filed over the weekend by the Brazilian bar association -- a stinging rebuke for Temer, a constitutional lawyer.
Meanwhile, Temer is scrambling to hold together his center-right PMDB party's ruling coalition to prevent impeachment and fend off pressure to resign.
So far, only smaller parties have jumped ship, but the PMDB's biggest ally, the PSDB social democrats, is wavering.
And on Wednesday, the Supreme Court is due to rule on Temer's request for the probe into his alleged obstruction of justice to be suspended due to supposed tampering of the incriminating tape recording.
The crisis -- linked to a gigantic corruption investigation targeting scores of top politicians -- threatens Brazil's attempts to exit the trauma of last year's Rousseff impeachment and a severe recession.
For now, most of the action is taking place behind the scenes.
A source with the presidency told AFP that Temer's coalition is holding. "The president is very conscious that he did nothing illegal and various leaders said they are standing firm," said the source, who asked not to be identified.
The vital PSDB had been due to meet with other coalition partners on Sunday, reportedly to consider the announcement of their mass departure. But the meeting was cancelled, giving Temer a breathing space.
On Monday, senior PSDB member and former president Fernando Henrique Cardoso said that the party's initial impulse to abandon Temer immediately should be rethought.
"I think it would be opportunism to go running," he told TV Bandeirantes. The PSDB "has responsibility."
However, if evidence against Temer is verified, "he would have a moral obligation to resign," Cardoso said.
The key evidence is the now infamous recording of Temer and Batista.
The president says the recording has been tampered with. However, a source at the prosecutor's office, who asked not to be identified, insisted that "the evidence is robust."
"It's not just audio -- there are documents, bank accounts, dates," the source said.
In his interview with Folha, Temer lambasted Batista for allegedly profiteering from the scandal, which sent the Brazilian currency down and put JBS shares into a tailspin.
On Monday in Sao Paulo, shares in the world's biggest meatpacking company fell more than 20 percent.
"I feel calm, especially as I said: I will not resign," Temer told Folha.
"If they want to, then they have to force me out, because if I resign, that is an admission of guilt."
Throughout the two-page spread interview with Folha, Temer struck a confident, defiant note. He even joked that his two brief, angry speeches on national television to declare his innocence had burnished his usually aloof image.
"I think they liked this new type," he said. "People think that I... that 'at last we have a president.'"