The two brothers accused of running Colombia's Cali cocaine cartel are nearing an agreement to plead guilty in exchange for guarantees that other family members won't face charges and will have access to some of the $2.1 billion the government wants to seize, The Associated Press has learned.

Gilberto and Miguel Rodriguez Orejuela would likely spend the rest of their lives in U.S. prison under the tentative deal, according to federal law enforcement officials and attorneys familiar with the negotiations. They spoke on condition of anonymity because the agreement was not finalized Friday.

The pleas would cap a massive 15-year U.S. investigation into the Cali cartel, which made more than $2 billion in profits by smuggling some 250 tons of cocaine into the United States since the 1970s. More than 100 other members of the cartel have been convicted since 1991.

The guilty pleas by the brothers and release of the final agreement could come as early as Tuesday, the officials and attorneys said. As of Friday morning, U.S. District Judge Federico Moreno had not scheduled a change of plea hearing, according to his office.

If the deal is completed, 28 family members in Colombia would receive guarantees that none would be extradited to the United States and prosecuted. They would be removed from a U.S. Treasury Department list that freezes assets of suspected drug traffickers and bars them from doing business in the United States.

The family members also would be permitted to keep houses and other assets in Colombia under the deal that involves agreements with the government in Bogota, according to the officials and attorneys. Specific details about those assets and amounts were not immediately available, but family members do have property and interests in legitimate businesses worldwide.

U.S. Attorney R. Alexander Acosta's office declined comment. Attorneys for the Rodriguez Orejuela brothers and their family members confirmed that an agreement resolving the case was imminent but declined to discuss details.

"The parties have worked feverishly to reach a resolution in this case that benefits everybody," said Roy Kahn, who represents Miguel Rodriguez Orejuela, 62. "I expect that a final resolution will come to light shortly."

David Oscar Markus, attorney for Gilberto Rodriguez Orejuela, 67, used a sports analogy to describe the status of the talks. "We are at the 1-yard-line and anticipate resolving this matter shortly," he said.

"We are moving forward and hopeful to have an agreement among all parties," added Marc Seitles, the Miami attorney for the Colombian family members.

Claudia Rodriguez Mondragon, daughter of Gilberto Rodriguez Orejuela, told The Associated Press in Bogota that there was nothing definitive yet but that the "family was waiting for lawyers and judicial authorities to finish their work so that next week (her father and uncle) could decide whether or not to sign" a plea agreement.

The tentative deal is the product of months of intense negotiations between the U.S. Justice, Treasury, State and Homeland Security departments, defense attorneys and lawyers for the family members and government officials in Colombia.

The brothers were convicted of drug charges in Colombia in 1995 and sent to prison there but were extradited to the United States to face a federal indictment alleging they continued to run their empire from prison. Colombia and the U.S. signed a new extradition treaty in 1997 that has led to more than 300 drug traffickers facing U.S. justice.

Federal prosecutors had been seeking forfeiture of $2.1 billion in assets linked to the brothers.

Miguel Rodriguez Orejuela's son, William Rodriguez Abadia, pleaded guilty in March to taking over much of the cartel's operations after the 1995 arrests of his father and uncle. Rodriguez Abadia agreed in his plea deal to testify for the government and to forfeit some $300 million in assets linked to drug profits, including his interest in the Drogas La Rebaja pharmacy chain, which has 350 stores in Colombia.

Rodriguez Abadia, 40, was sentenced to over 21 years in U.S. prison an agreement that granted his wife, two children and mother-in-law permanent legal residency in the United States.