State bank BNDES is organising finance for the US$9bn scheme, known as TAV (Trem de Alta Velocidade), which will connect tens of millions of people on Brazil’s southern coast.
The line between São Paulo and Rio de Janeiro is expected to be built over five years and will cover 510km in total.
"This may be the country's most important infrastructure project this century," said Howard Steinburg, partner at financial advisors Shearman & Sterling, which is advising BNDES on the project.
Shearman & Sterling is working with Brazilian public law specialist firm Manesco, Ramires, Perez & Azevedo Marques on the bidding process.
According to the government schedule, pre-qualification documents will be analysed and the bidding auction will take place on 16 December.