Network Rail is looking for contractors for a deal worth up to £1.24bn in north-east London and the East Midlands.
The successful contractors will form an alliance with Network Rail.
The project will cover control period 5, which runs from 2014 to 2019, but Network Rail could extend it to control period 6, which covers 2019 to 2024, and even to 2025.
The total work undertaken through the deal is expected to be worth £240m to £1.24bn.
The contract is divided into four lots: signalling and communications, worth £52.8m to £272.8m; track construction and demolition, worth £88.8m to £458.8m; construction, worth £62.4m to £322.4m; and electrical, plant mechanical and overhead line work, worth £36m to £186m.
Contractors bidding for more than one lot will only be invited to tender for their preferred one.
Successful bidders cannot enter into joint ventures, partnership or other sharing arrangements with other alliance members and they must accept joint and several liability.
Network Rail will pay each contractor its actual cost each month. It is carrying out a separate tender for a lead design organisation to join this alliance.
Contractors must have a turnover of at least £10m to be considered. The deadline for tenders or expressions of interest is 2 December at 1pm.
More information is available from www.networkrail.co.uk and from Christopher Pybus, Infrastructure Projects, Scotland & North-east, Network Rail Infrastructure Limited, Northern House, Rougier Street, York, YO1 6HZ, firstname.lastname@example.org