The announcement of Lucibello's decision came one day after William Andrews, a South Philadelphia drug dealer and reputed mob associate, entered a guilty plea in an unrelated drug case.
Andrews has been described as a close associate of mob underboss Joseph "Mousie" Massimino, another defendant in the Ligambi case.
Neither Lucibello nor Andrews is cooperating with authorities.
Andrews, who served 12 years in prison for a drug-dealing conviction, is looking at a sentencing range of 12 to 15 years, according to his plea agreement.
While details of Lucibello's plea deal have not been made public, sources said he had agreed to a deal that will result in a sentence of about five years.
Lucibello's court-appointed attorney could not be reached for comment Thursday.
Federal prosecutors are expected to file a plea memo detailing the agreement before Tuesday's hearing. In a pretrial detention motion filed shortly after his arrest, prosecutors described Lucibello as a "long-standing soldier" in the Philadelphia crime family.
Lucibello, like Ligambi, Massimino, and several other key defendants, has been held without bail on racketeering-conspiracy charges. He is accused of extortion and running an illegal video-poker machine business for the mob.
The government detention motion said that the case against him was built around "the testimony of cooperating witnesses, recorded conversations, and surveillance evidence." Among other things, Lucibello was charged with collecting a "street tax" from an unnamed bookmaker on Massimino's behalf after Massimino was jailed on racketeering charges in New Jersey in 2004.
Lucibello, after reviewing the evidence, apparently decided to take a plea rather than argue his case in front of a jury. Robreno, who has a reputation for handing down tough sentences, had scheduled a Sept. 4 trial date.
Among other things, sources said, Lucibello was concerned and disappointed that longtime gambling associate Jack Buscemi had apparently agreed to testify for the government.
Authorities have described Buscemi, of Mullica Hill in Gloucester County, as one of the biggest bookmakers in the Philadelphia area. He was implicated in an illegal sports-betting operation run out of the Borgata Hotel Casino in 2007 and sentenced to five years in prison. He served less than a year.
New Jersey authorities at the time said Buscemi reported to Lucibello.
After being denied bail at a hearing in May, Lucibello told friends as he was led away in handcuffs, "I beat 'em before, I'll beat 'em again."
But after about a year in the Federal Detention Center in Philadelphia, he apparently has decided to give up the fight.
At his trial in 1996, Lucibello beat more serious racketeering charges that tied him to several gangland murders.
Taking the witness stand in his own defense, he denied he was a member of the mob or had taken a loyalty oath to La Cosa Nostra.
"I'm loyal to me," Lucibello said under questioning from his defense attorney, F. Emmett Fitzpatrick.
Contact staff writer George Anastasia at 856-779-3846 or firstname.lastname@example.org.