The Colombian Government has set up a new team of consultants and specialists to oversee the estimated $440m Sistema Ferroviario Central railway concession.
The move follows a corruption scandal in the tender process, which led to its suspension in September.
The project involves building a 1,050km railway from La Dorada to Chiriguaná, linking Colombia's central area to the Santa Marta port on the Atlantic coast.
The winning team will build the La Dorada stretch, renovate the stretches connecting the districts of La Dorada and Buenos Aires, Puerto Berrío and Envigado and La Dorada and Facatativa, and maintain the Chiriguaná-Buenos Aires rail stretch.
The team will also provide passenger and cargo transport services over a 30-year period.
The railway is expected to handle half of the cargo transported along the country's central corridor.