Guatemala City (CNN) -- Disgraced, imprisoned and facing money laundering charges in the United States, former Guatemalan President Alfonso Portillo is reigniting his defense.
The leader of Guatemala from 2000 to 2004, Portillo has always denied the charges against him and now says the accusations are based on the lies of political enemies seeking revenge.
"It is revenge that was organized and a result of a conspiracy among certain sectors, as much those in economic power in Guatemala as my enemies and ideological adversaries in the United States, to get revenge against me and remove me from the political scene," Portillo said in an exclusive interview with CNN en Español broadcast Thursday morning.
Chain-link fences and barbed wire surrounded him as he spoke to the network from the courtyard of a Guatemalan prison this week.
In addition to airing his grievances with the media, Portillo said earlier this month that he will file a complaint before the Inter-American Court of Human Rights, alleging that his rights have been violated by authorities. He alleges he was denied due process in his first extradition from Mexico to Guatemala in 2008 and by a second extradition request by the United States.
Portillo said right-wing political adversaries in the United States engineered the charges against him.
"In the United States it is a revenge of the richest group of the American right. They are charging me for being the only president who did not support with his signature nor with his permission the invasion in Iraq," Portillo said. "So, I know that it is not only illegal. I know that it is eminently political, my detention in Guatemala."
But U.S. prosecutors have said it was Portillo who abused the political system, accusing him of using his authority to launder and misappropriate millions of dollars intended for his country's people.
"Portillo is charged with converting the office of the Guatemalan presidency into his personal ATM," Preet Bharara, U.S. attorney for the southern district of New York, said in a 2010 statement. "Through various alleged embezzlement schemes, including one which involved $1.5 million intended for Guatemalan school children, Portillo abused the trust of his nation's people."
An indictment unsealed in New York federal court accuses Portillo of embezzling tens of millions of dollars worth of public funds, "a substantial portion of which he laundered through American and European bank accounts."
After the United States made an extradition request, Guatemalan authorities arrested him on a farm on the country's coast in 2010.
Guatemalan courts and the country's president authorized his extradition to the United States in 2011, but the transfer has yet to take place.
A U.S. State Department spokeswoman declined to comment on the status of the extradition case.
Portillo told CNN en Español that he never laundered money in U.S. banks.
"If deposits were made," he said, "they are deposits that first of all come from institutions that are not illicit. In order for there to be laundering, the first requirement is that the money is from an illegal origin or comes from an illegal activity."
Guatemalan courts have previously acquitted Portillo of embezzlement allegations -- something that Portillo says shows that the U.S. accusations against him are baseless.
Portillo responded directly to the charge concerning the $1.5 million that the United States says was intended for school children. That money, Portillo said, was something he had requested and received before he became president. From the beginning, that money was raised to create a trust fund to support his daughter's studies, and that is what it was used for, Portillo said.
Despite his claims that his rights have been violated during the extradition process, Portillo said he believes he will get a fair trial in the United States.
"I have confidence that at least I will have a transparent, impartial, objective trial that is based on reliable evidence and not just testimonies that are based on falsehoods," he said. A fair trial would not be possible in Guatemala, he added.
In the meantime, prison life hasn't been too bad, the former president said.
"I think pain and suffering make men better, make women better, make human beings better," he said.
In the three years he has spent in prison, he has read more than 100 books and seen more movies, he said.
"I don't regret anything. And I know this has some purpose. It will accomplish something in my life," Portillo said. "Let God decide my destiny, and let history condemn or absolve me."
Journalist Miguel Salay reported from Guatemala City. CNN's Catherine E. Shoichet reported from Atlanta. CNN's Mariano Castillo contributed to this report.