The financial newspaper Valor Econômico previously reported that the Brazilian authorities were exploring whether JBS profited from trades related to the market turmoil around Mr. Batista’s plea deal. JBS said in a statement that its trading activities were legal.

Mr. Temer also claimed on Saturday that Mr. Batista’s recording of their meeting one evening in March at the president’s residence in the capital, Brasília, had been “manipulated and adulterated.” Mr. Temer said he was issuing a request to the Supreme Court to suspend the investigation into him.

JBS said that the recording was not adulterated, adding that Mr. Batista and other executives from the company had provided an array of documents to support their testimony in plea negotiations.

Analysts did not think the televised speech would do much to help the president’s position.

“This does not reduce the political crisis and does not improve Temer’s situation,” said Paulo Baía, a professor of political science at the Federal University of Rio de Janeiro, describing the president’s strategy as trying to disqualify his accuser and the evidence that Mr. Batista provided about Mr. Temer.

“Temer is in intensive care, in a very serious state, trying to survive,” Mr. Baía said.

Indeed, the investigation of Mr. Temer is the deepest crisis of his brief presidency. Allies of Mr. Temer have been forced to resign over claims that they tried to stymie corruption inquiries, but Mr. Temer has had some success in persuading lawmakers to approve austerity measures aimed at shoring up confidence in the economy.

Mr. Temer was already governing under the cloud of scandal, facing testimony that he negotiated a $40 million bribe for his scandal-ridden Brazilian Democratic Movement Party in 2010. Mr. Temer, who has struggled with dismal approval ratings, has denied the claims.

But while Brazil’s Constitution prevents sitting presidents from being investigated for acts committed outside their terms in office, Mr. Temer is coming under intense scrutiny over the latest claims. In Mr. Batista’s recording, Mr. Temer seems to be heard endorsing bribes of a jailed politician who helped orchestrate Ms. Rousseff’s ouster, as Mr. Batista brags about buying off a prosecutor and a judge.