The South Australian dubbed "Cocaine Cassie" has been given an ultimatum by Colombian authorities - provide details of the drug-smuggling ring she allegedly worked for, or spend 30 years locked up.

Cassie Sainsbury has been behind bars in a maximum security jail in the Colombian capital Bogota since her arrest in April. A former personal trainer, Sainsbury was caught with 5.8kg of cocaine inside 18 headphone cases in her luggage at El Dorado International Airport in Bogota on April 11.

The 22-year-old continues to deny wrongdoing and will face another court hearing later this week. But behind-the-scenes authorities are attempting to find out who Sainsbury worked for, the Adelaide Advertiser reports.

Colombian authorities are demanding to know who supplied the drugs found in her luggage and want more details of the failed trafficking operation.

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"Cocaine Cassie" with the 5.8kg of cocaine she is accused of smuggling into Bogota. Photo/AP

According to the Advertiser, without that information prosecutors will not honour any plea bargain which would potentially reduce a 30 year sentence to one of about four years.

If Sainsbury does go through with the deal though it could mean she has to enter a witness protection program to protect her from revenge attacks by members of the drug cartel.

She was on her way to the United Kingdom when she was prevented from boarding. At first she claimed she bought the headphones as gifts for her bridal party.

Some members of her family later alleged a Colombian drug cartel threatened her so she would smuggle the drugs for them.