The Société du Grand Paris is to tender for the first major civils contracts for Line 15 South of the Gand Paris Express later this year.
The authority has published a preliminary information notice in the Official Journal of the European Union setting out the scope of the works involved for the planned 33-kilometre underground metro.
Line 15 South will be divided into eight main works contracts for which bidding will begin in the second quarter of 2015 and continue until the second quarter of 2016.
Contracts will cover station and tunnel construction and associated works.
Five to seven bids will be selected for each process, Société du Grand Paris has said.
By 2030, Paris will have four brand new metro lines (15, 16, 17 and 18) plus extensions to lines 11 and 14. The new orbital network will allow passengers to travel between Parisian suburbs without going through the city centre, significantly reducing existing journey times.