NEW YORK (AP) — Closing arguments began Wednesday in the trial of a U.S.-educated man from Iran who is accused of violating the Iran trade embargo in a case that puts a spotlight on the informal money transfer business in South Asia known as an "hawala."

Assistant U.S. Attorney Danya Perry detailed the evidence the government has presented against Mahmoud Reza Banki as she asked the jury in federal court in Manhattan to convict him of conspiracy and other charges.

She said Banki played a "critical role" by serving as the U.S.-based arm of a money transfer business that paid out money in Iran each time money was placed into Banki's bank accounts in the United States.

Perry said funds were transferred illegally into Banki's accounts "over and over and over again over several years."

Prosecutors say Banki, who had worked for management consulting firm McKinsey & Co., bought a $2.4 million Manhattan condominium and made payments on his credit card accounts with much of the $3.4 million deposited into his bank account.

Banki, a U.S. citizen who has been held without bail since his January arrest, faces up to 25 years in prison if he is convicted of all charges. His defense lawyer was scheduled to present his closing argument Thursday.

The defense was expected to cite the testimony of Banki's mother, Forooz Banki, to show that money moved into Banki's accounts was an effort by the family to move portions of its fortune to the United States to keep it away from her ex-husband after he had an affair.

The mother testified during the last week that her ex-husband brought Reza Banki to the United States 16 years ago to attend school. He attended Purdue University and the University of California at Berkeley and got a doctorate in chemical engineering from Princeton University.

She testified that she divorced her husband in 2005 "after another lady came into our life."

Jurors were shown a videotape of a meeting at around the same time in which Forooz Banki, her two sons, and their father discuss the divorce and finances with her brother, who she testified directs the family's three Iranian power companies and a pharmaceutical company.

"I personally myself wanted to have financial security," she testified. "And the children were concerned about the finances and, because (of) the problem that had occurred, they didn't want the father to lose the money," she said.

The mother testified that her ex-husband reluctantly went along with a plan to buy an apartment in the United States and invest money there.

"Because of the mistake that he had made, he didn't want to lose his children and ruin his life," Forooz Banki said.

The desire to move family money to the United States as a result of the family troubles was a key part of the defense presentation during its opening.