Companies are invited to submit bids for two new contracts worth more than £500m for phase two of the high-speed rail network.
HS2 is seeking bids from companies interested in one contract or the other as bids from the same firm for both deals are not allowed.
The first contract is worth between £130m and £170m and is for a phase two development partner to provide project management services and support in managing professional service contracts.
HS2 has specified an estimated contract length of 90 months – or seven-and-a-half years – for the partner in question.
Due to the resources, range and depth of skills required to undertake the contract, HS2 has suggested the applicants may wish to combine and form consortia or, alternatively, apply as the main consultant and rely on sub-consultants to deliver some of the services.
The second contract, worth between £280m and £350m, is for professional services consultants to deliver civils designs and environmental services, as well as environmental overview consultant services.
That contract is split into three lots, each dealing with a different geographical area.
The largest of those is the third lot, worth between £120m and £150m, which covers civils design and environmental services in Leeds.
All interested parties have until Monday, April 25 to make a bid; further information is available at www.hs2.org.uk