The charge relates to Weiner's "sexting" scandal in which he exchanged sexually explicit text messages with a 15-years old girl last year.
Several media outlets reported that Weiner checked into a rehabilitation center to undergo sex addiction treatment following the incident.
"I have a sickness", Weiner said, "but I do not have an excuse". His wife Huma Abedin was a top aide to Hillary Clinton, and it was during the probe into Weiner that the FBI found emails on a laptop that related to a past investigation into Clinton's email practices. According to The Times, the plea agreement could result in Weiner registering as a sex offender but avoiding prison time - the charge he's facing carries a possible sentence of up to 10 years in prison.
Former U.S. Congressman Anthony Weiner wept on Friday as he pleaded guilty to sending sexually explicit messages to a teenage girl, ending an investigation into a "sexting" scandal that played a role in last year's U.S. presidential election.
Weiner will plead guilty to a single charge of transferring obscene material to a minor, the New York Times reported.
David Schaefer, a spokesman for the law firm Covington & Burling, whose attorney, Arlo Devlin-Brown, is representing Weiner, said the former congressman's lawyer will comment later Friday.
The online sexting relationship allegedly went on for months between Weiner and a girl claiming to be just 15.
The investigation into Weiner ended up intruding on last year's presidential campaign. The two married in 2010, and in June 2011 Weiner resigned from Congress, a month after the release of an explicit photo of him that he inadvertently posted on his Twitter account. Phone messages left Friday with the North Carolina girl's father were not immediately returned.
The cache of emails prompted then FBI director James Comey to make his now infamous decision to reopen the previously closed investigation into Clinton's alleged mishandling of classified material.
Weiner, who lives in Manhattan and represented NY in Congress from 1999 to 2011, resigned after revelations that he was sending sexually explicit messages to multiple women. Comey announced shortly before the election that the new emails contained nothing to change his view that Clinton could not be charged with a crime. But Clinton partly blamed her election loss to Republican Donald Trump on Comey's announcement. Weiner attempted to run for mayor of New York City in 2013; however, the effort was derailed after more explicit messages surfaced.
His failed mayoral bid is the subject of the documentary "Weiner".