The two UK women arrested in Peru last month trying to board a flight to Spain with 24lb of cocaine in their luggage face a minimum of six years and eight months in prison with no eligibility for parole if they plead guilty, the prosecutor handling their case said.
He added that a further sentence reduction is possible if the women co-operate as witnesses against co-conspirators.
Michaella McCollum, 20, from Dungannon, Co Tyrone, and Melissa Reid, 20, from Lenzie, have a court hearing on Tuesday where they are expected to be interrogated by a judge.
Mr Mendoza said that, if both women plead guilty, they could be sentenced to prison in less than a month, otherwise their trial could last six months.
A new law, enacted two weeks after the women’s arrest, eliminated sentence reductions for good behaviour for people convicted of drug trafficking.
Previously, parole was possible after 32 months for drug couriers who pleaded guilty.
Mr Mendoza said he did not believe that they were coerced into carrying the drugs or in any way threatened.