Mr. Zarrab also testified that he had paid tens of millions of dollars in bribes to the country’s then economy minister, Zafer Caglayan.
Before Mr. Zarrab secretly pleaded guilty on Oct. 26 to conspiring in the sanctions scheme, he was to have been tried along with Mr. Atilla. His plea and cooperation agreement were revealed last week when the trial began.
On Tuesday, during his cross-examination, Mr. Zarrab offered new details about an unrelated charge to which he also pleaded guilty — bribing a guard at the Metropolitan Correctional Center, where he was held, in return for contraband like alcohol and for the use of the guard’s cellphone.
Mr. Zarrab revealed Tuesday that the bribe was about $45,000, and said the payment had been arranged by a lawyer in Turkey who was representing him and was in New York at the time. Mr. Zarrab did not identify the lawyer; one of his New York attorneys, Robert J. Anello, declined to comment. A jail spokesman did not immediately respond to a request for comment.
Mr. Zarrab’s testimony, now in its second week, continued to send political tremors through Turkey.
Mr. Erdogan used his weekly address to parliamentarians from his Justice and Development Party on Tuesday to make a heated attack against the United States. He pointed to not just the trial, but also American support for Kurdish insurgents in Syria and United States policy in Israel.
“It is now understood that the U.S.A. has a plan against us,” Mr. Erdogan told legislators. “It is obvious that this trial is brought up as a tool to blackmail us to give up our claims in the region.”
Mr. Erdogan, who values his personal relationship with President Trump, suggested that holdovers from the Obama administration still in the United States government were trying to undermine the Trump administration.
“This trial is also a piece of the big fight, the big strife in American domestic politics,” Mr. Erdogan said. “American media covers this trial alongside with the ‘Russia, Flynn, Trump’ headline.”
Mr. Erdogan noted that the sanctions case indictment says “conspiracy.”
“Yes, there is conspiracy — but against Turkey,” he said. As he has repeatedly in the past, he blamed followers of the cleric Fethullah Gulen, who he has accused of fomenting a failed coup against him in 2016.
And in a warning to opponents at home, Mr. Erdogan said: “Whoever takes the trial in America as a matter of domestic politics is a collaborator in the treachery.”
During Mr. Zarrab’s cross-examination, he also revealed that his lawyers first met with prosecutors as early as the summer of 2016 to discuss the possibility of his cooperating with the government, but the idea went nowhere. Then, this past August, he and his lawyers met with the government, leading to about a dozen sessions with prosecutors and F.B.I. agents, after which the government agreed to the cooperation deal.
Mr. Zarrab also testified about his efforts before becoming a government witness to have his lawyers in Turkey and New York try to resolve his case outside of the court system. “Within the bounds of law, they did make efforts,” he said in response to a question from Cathy Fleming, a lawyer for Mr. Atilla.
“In fact, you hired Rudy Giuliani and former Attorney General Michael Mukasey as your attorneys in the United States to try to work out a solution for you in Turkey, correct?” Ms. Fleming asked.
“That is correct, ma’am,” Mr. Zarrab said.
“In fact, you are furious with people in Turkey that it did not work, isn’t that true?” Ms. Fleming asked.
“I don’t have any anger towards anybody, ma’am,” Mr. Zarrab replied.