PORTLAND, Ore. —  The son of an imprisoned ex-CIA spy claims he was "just the messenger" when he traveled around the world taking cash from his father's former Russian handlers, according to taped phone conversations played in court Tuesday.

Federal prosecutors played the recordings of Nathaniel Nicholson talking to friends and relatives, telling them the FBI had interviewed him but he had done nothing wrong and did not expect to go to prison.

At one point, an unidentified friend says Russians "have cool accents" and asks, "We're not like, against the Russians, are we?"

Nicholson and his father, Harold Nicholson, have pleaded not guilty to charges of conspiring to act as agents of a foreign government and money laundering. Prosecutors say the younger Nicholson traveled on behalf of his father, who pleading guilty in 1997 to conspiring to commit espionage after being paid $300,000 to pass CIA secrets to the Russians, including the identities of other CIA officers and recruits he had trained.

Harold Nicholson is accused of tapping his old contacts for more money by sending his youngest son to San Francisco; Mexico City; Lima, Peru; and Nicosia, Cyprus, between October 2006 and December 2008.

The elder Nicholson's former handlers were trying to figure out how he had gotten caught and how much U.S. agencies had learned about Russian spying, investigators said when he was indicted in January.

On the recordings, Nathaniel Nicholson describes taking more than $45,000 from Russian officials, but he repeatedly says he does not believe he has done anything wrong.

He also tells his sister, Astralena, that he passed along some of the money to her and their older brother, Jeremiah.

"Dude, I never thanked you for the money," she says. "I thought it was from daddy."

In the taped conversation, Nathaniel Nicholson also says he lied to his sister to protect her. He says he took messages to the Russians on tissue paper he smuggled out of prison during visits to his father.

"You don't have to worry about anything on your part or anything like that 'cause you guys, you know, haven't done anything," he tells her.

When she asks whether he has become a "snitch" against their father, Nathaniel Nicholson tells her, "I didn't even know what the information was," adding that "it was nothing illegal or anything like that."

Astralena Nicholson was in court Tuesday, but declined comment, as did one of her cousins.

Transcripts of other recorded conversations between Nathaniel Nicholson and his sister were also released at the detention hearing.

U.S. District Judge Anna Brown did not rule on whether to release Nathaniel Nicholson, but she repeatedly asked prosecutors whether electronic monitoring would be sufficient.

Prosecutors argued Nathaniel Nicholson was a flight risk because he faces a maximum of about 100 years in prison if convicted of all charges.

But defense attorneys argued he was not a risk because he has been cooperating with the FBI and is "contrite and apologetic." They said the telephone transcripts show his devotion to his family.

FBI agent John Cooney testified Tuesday that he and fellow agent Jared Garth interviewed Nathaniel Nicholson at his apartment on Dec. 15, 2008, and questioned him about his travels.

Cooney said he repeatedly warned the younger Nicholson that it was a crime to lie to federal agents and that his account of his travels conflicted with evidence obtained during the investigation.

"Essentially he had lied to you up to that point, and you gave him a chance to come clean?" Assistant U.S. Attorney Pamala Holsinger asked Cooney.

"Yes," Cooney replied, saying he used the analogy of a "mulligan," or a "do-over" golf shot.

Cooney said Nathaniel Nicholson eventually changed his story and signed a detailed statement. He was arrested Jan. 28.

Harold Nicholson is serving a sentence of more than 23 years at the federal prison in Sheridan, just south of Portland.

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