Prosecutors say one of Colombia's most notorious reputed cocaine kingpins is set to plead guilty next week to U.S. drug charges.

A Miami federal judge on Friday set a change of plea hearing for Tuesday for "Don" Diego Montoya, the alleged chief of Colombia's North Valley Cartel. Montoya was extradited to face U.S. charges in December and initially pleaded not guilty.

Prosecutors say in court papers that Montoya will plead guilty to charges from two separate cases: one in Miami and one in Washington, D.C. Both accuse Montoya of drug racketeering and conspiracy charges.

Montoya's attorney did not immediately return a telephone call seeking comment.