(CNN) -- A New York imam who pleaded guilty to lying to federal agents as they investigated an alleged terror plot left the United States on Monday as part of his plea deal, a government spokesman and the imam's attorney told CNN.
Imam Ahmad Afzali and his wife left on a 2 p.m. flight to live in Saudi Arabia, said Afzali's attorney, Ron Kuby.
A government spokesman confirmed Afzali's departure.
After his guilty plea earlier this year for lying to federal agents in the case involving Najibullah Zazi's alleged subway bombing plan in New York City, Afzali had 90 days to "self-deport" from the United States and was required to wear an ankle monitor until his departure, according to Kuby. The ankle monitor was removed before Monday's flight, Kuby said.
"Imam Afzali did his best to assist authorities when they asked for his help," said Kuby, who claimed Afzali was the victim of a turf war between the New York Police Department and FBI over the terrorism investigation.
"For his part, he leaves the United States with great sadness and no bitterness," Kuby said. "The United States is the only home that he knows; this country remains home to his parents, his children, and his brothers."
Zazi and two other suspects planned to attack trains at New York City's Times Square and Grand Central stations, according to a law enforcement source.
Afzali, a Muslim cleric and funeral director from the New York borough of Queens, was originally charged in a four-count indictment in the Zazi case.
He pleaded guilty to one charge of lying about whether he tipped off Zazi that the FBI had been asking questions about Zazi's activities. Zazi subsequently pleaded guilty to conspiring to detonate explosives in the United States.
During a plea hearing in March, Afzali told the court that police had asked him to help provide information about Zazi and two other suspects, Adis Medunjanin and Zarein Ahmedzay. He said he knew Zazi and Medunjanin fairly well from when the men were teenagers and would attend his mosque for prayers and to play volleyball.
"The police interest in these men led me to believe that they were involved in some criminal activity, but I had no idea of its seriousness," Afzali said after his March plea hearing.
He said he called Zazi on September 11, 2009, a day after he was contacted by authorities.
"I told him that our phone call was being monitored," Afzali said. "I told Zazi, 'Don't get involved in Afghanistan garbage and Iraq garbage, that's my advice to you.' "
Two days later, Afzali said, he was interrogated by FBI agents for the first time.
"I believed that the FBI was angry at me for calling Zazi," he added. "When I was asked whether I had told Zazi about law enforcement being interested in him, I lied and said I did not. My intention was not to protect Zazi but to protect myself."
He admitted to repeating the lie during another interview with prosecutors a few days later, saying, "In doing so, I failed to live up to my obligation to this country, my community, my family and my religion. I am truly sorry."
The two other suspects in the case, Ahmedzay and Medunjanin, pleaded not guilty in February to new charges of conspiracy to use weapons of mass destruction against persons or property in the United States, as well as several other counts. The two had previously faced lesser charges.
Prosecutors say the men -- 25-year-old U.S. citizens and residents of Queens -- conspired with Zazi "to attack the New York subway system in mid-September 2009." A fourth suspect in the case is in custody in Pakistan, according to a law enforcement source.
CNN's Eden Pontz and Susan Candiotti contributed to this report.