High Speed Two (HS2) Limited has invited nine companies to tender for a works package worth £11.8 billion.

Initially shortlisted in March this year, the nine firms have all been invited by HS2 officials to tender for the civil engineering package for the first phase of the project, which will cover Birmingham to London, and is worth up to £8.6 billion.

Further on in the tendering process, firms who have been successful will then be eligible to start bidding for a phase 2a, which is worth another £1.8 billion – £3.3 billion of work. This phase will cover Crewe to Birmingham.

The companies have each been invited to tender for the work packages, which include Long Itchington Wood Green tunnel to Delta Junction / Birmingham Spur (£900m-£1.5bn) and Chiltern tunnels and Colne Valley viaduct (£800m-£1.3bn).

It is expected that the civil engineering contracts that will cover the 225km first phase of the scheme will be signed next year, with work set to begin on site the following year.

Overall, phase one of HS2 is expected to create almost 15,000 jobs and apprenticeships in the construction industry.

Meanwhile, David Cameron recently said that a Brexit vote would result in both HS2 and HS3 schemes being under threat.

He said that if the UK elects to leave the European Union on June 23, this could lead to and end of the proposed investment levels in the rail sector.

He added that while the Government would still try to maintain investments in the projects if we leave the EU, this would pose a significantly greater challenger than if we were to remain.

Earlier in the year, Chancellor George Osborne said that £60 million would be funded into rail in order to make the connection between Manchester and Leeds faster by 30 minutes.

The current budget for HS2 is £55.7 billion and is a major part of the Government’s ‘northern powerhouse’ scheme.