The winners of £6.6bn worth of contracts to build the first phase of HS2 between London and Birmingham have been announced by the government.
UK firms Carillion, Costain and Balfour Beatty are among the consortiums who will build tunnels, bridges and embankments on the first stretch of the new high speed rail line.
The contracts will support 16,000 jobs.
The final routes of the Manchester and Leeds branches of HS2 are due to be announced later.
It will include a decision over its path through Sheffield.
Transport Secretary Chris Grayling said: “As well as providing desperately needed new seats and better connecting our major cities, HS2 will help rebalance our economy.”