GREENBELT, Md. (AP) — Former Trump administration national security adviser John Bolton pleaded guilty on Friday to illegally retaining classified information, sealing a deal with federal prosecutors that could allow him to avoid a prison term.

Bolton, who became an outspoken critic of President Donald Trump after serving in the Republican's first administration, is scheduled to be sentenced on Oct. 28 by U.S. District Judge Theodore Chuang in Greenbelt, Maryland.

Bolton, 77, of Bethesda, Maryland, pleaded guilty to a single count of illegally retaining national defense information, which carries a maximum sentence of 10 years. His plea agreement with the Justice Department may enable him to avoid time behind bars, but the judge ultimately will decide his punishment.

The plea agreement recommends capping any prison sentence at five years, but the judge isn't bound by that part of the deal. Bolton, who also agreed to pay a fine of $2.25 million, can withdraw his guilty plea if the judge imposes a longer prison sentence or a larger fine.

WATCH: Former Trump adviser John Bolton to plead guilty over classified information

Bolton must pay half of the fine within five days of his plea and the balance within 90 days. He agreed to forfeit his retirement pay for his federal service. The plea deal also requires him to submit to a debriefing with federal intelligence officials and perform up to 100 hours of community service.

After a prosecutor read aloud a summary of his offenses, Bolton agreed that it was accurate.

"I'm sorry for it," he told the judge.

Defense attorney Abbe Lowell said Bolton "did what real leaders do" by pleading guilty.

READ MORE: What to know about the federal charges against John Bolton

"He took responsibility for a mistake he made, thereby saving the government resources to pursue a case that could expose additional sensitive information," Lowell said in a statement after the hearing.

U.S. Attorney Kelly O. Hayes, the top federal prosecutor for Maryland, said Bolton knew how to properly handle and store classified information.

"He also knew the damage to national security that could be caused by mishandling that sensitive information. Nevertheless, as Mr. Bolton just admitted, he put our national security at grave risk in violation of the law," Hayes told reporters.

Bolton was charged last October with 18 counts of either retaining or disseminating classified information, including diary-like notes that he shared with relatives as he wrote a memoir about his career in government.

READ MORE: Read the full indictment of John Bolton, ex-Trump national security adviser turned critic

Other Trump adversaries have been charged with federal crimes during his second term in the White House. While some of those cases have collapsed under judicial scrutiny and amid claims of political retribution, Bolton didn't mount a vigorous defense against his charges before cutting a deal.

FBI agents searched Bolton's Maryland home and Washington, D.C., office last August, but the investigation began before Trump returned to the White House in January 2025.

Bolton served as national security adviser for more than a year in Trump's first administration before getting pushed out in 2019. He later published a book called "The Room Where it Happened" that presented an unflattering portrait of Trump's leadership.

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The Trump administration fought unsuccessfully to block the book's release, claiming it contained classified information that could jeopardize national security. Trump derided Bolton as a "crazy" warmonger who would have led the country into "World War Six."

Bolton's indictment focused on notes that he shared with his wife and daughter rather than the contents of his book. After sending one document, Bolton wrote in a message to his relatives, "None of which we talk about!!!" In response, one of his relatives wrote, "Shhhhh," prosecutors said.

Bolton shared over 1,000 pages of diary-style information about his daily duties as national security adviser with his family members, according to a court filing accompanying his guilty plea. There is no evidence that his relatives shared the information with anybody else.

However, sometime after Bolton left government service, a hacker linked to Iran accessed classified information from Bolton's personal email account, the court filing says. Bolton directed a representative to notify U.S. officials about the hacked account in 2021.

Associated Press writer Eric Tucker contributed to this report.