HS2 has begun contractor engagement for civils work on the phase 2a section between Birmingham and Crewe.
The client has not yet taken a decision on the procurement route for the contracts and is still considering the option of running a competition with existing suppliers.
As part of its contractor consultation measures, HS2 has launched a market engagement survey to gauge capacity in the industry for the 2a civils deals.
The comes after HS2 issued a prior information notice (PIN) last week notifying contractors of its intentions for the phase.
The client is expected to take a decision on which procurement route to take in 2019.
Values, timescales and the structure of contracts will be confirmed by HS2 at a later date, with the contract award to take place once the legislation for the section of the line has reached royal assent.
Phase 2a covers work on the first 58 km section of the western leg of phase two.
The route runs through several local authority districts, including Stafford, Stoke-on-Trent and Cheshire, though predominantly covers farmland.
Civils work will include 2.1 km of bored tunnels, 8 km of viaducts, 19m cu m of embankments, 20m cu m of cuttings, 61 bridges and one combined infrastructure maintenance depot.
Design work for phase 2a is expected to begin in 2019, with construction scheduled to commence in 2021.
Documents filed by the Department for Transport in August 2017 revealed that an estimated £3.2bn will be needed to cover the construction of phase 2a, including enabling works, civils and associated utilities.