New West Midlands mayor Andy Street has asked transport secretary Chris Grayling for a contribution of at least £207m towards the extension of the Midland Metro tram network.
Conservative Mr Street and Laura Shoaf, the managing director of Transport for West Midlands (TfWM), formally presented the business case for the new seven-mile extension to Mr Grayling at the House of Commons.
The document shows that the cost of the scheme, including new trams, has risen from £310m in 2015, when a £207m contribution was expected from central government, to an estimated total of £343.6m.
It states: 'For WMCA to fully meet the maximum £343.6m current estimated cost, other funding contributions will be required to cover any expenditure above the £310m.'
It notes that if no other sources of external funding become available to fully meet the £343.6m, local funding may be required, including prudential borrowing by WMCA which would require an additional increase in the Transport Levy on member authorities.
Mr Street said: ‘I said in my manifesto that starting work on this project during my first three years in office was a priority and securing the funding is the first step, which is why I wanted to see the secretary of state so quickly.
‘The leaders of the local authorities within the West Midlands Combined Authority have done a first class job in developing the plans to this stage. Now we need to secure the final funding.
‘It is hard to understate just how important this project is to the Black Country. The business case shows that for every pound invested in this project, it will return £2.50 for the local economy.'
He added: ‘This is the start of the conversation about how as a region we can look at new ways of working with Government to use new mechanisms of funding and finance to deliver transformational projects like this.’
The new line from Wednesbury to the new DY5 Enterprise Zone at Brierley Hill is the first of a series of proposed extensions to the route, which currently runs from Wolverhampton to Birmingham.
This includes extensions to Wolverhampton interchange and the HS2 terminal at Curzon Street in Birmingham. The Brierley Hill route forms part of longer-term ambitions to link the Black Country to the HS2 network.