The managing director of Alstom in Britain and Ireland has warned that the company’s Derby factory in Litchurch Lane will have run out of work by the end of January when the building of Aventra units is completed, and if it closes thousands of jobs will be lost.

Nick Crossfield was giving evidence in Westminster to the Transport Select Committee, which is preparing a report on the future of Britain’s trains.

While the Committee was in session, protestors from Derby and the union Unite were demonstrating outside.

Mr Crossfield said: ‘We finish the manufacturing programmes at the end of January – so in six weeks we go from an annual output of 650 cars employing 3,000 people to zero. The meter is running.’

There are also fears for the security of jobs in Alstom’s supply chain, much of which is in the East Midlands, and those fears are already proving justified. He continued: ‘Today, I have the supply chain showing liquidation. My paint supplier has gone into insolvency, a major on-site supplier providing the wiring loom employing several hundred people [has] announced at the end of January it is done.

‘The timing of these decisions is critical because if I don't get clarity in the next six weeks – it all goes.’

He also told MPs on the Committee that ‘there is a conversation to come’ about how the Prime Minister’s decision to abandon HS2 to Crewe and Manchester will affect the order for rolling stock on the high speed line, which was won jointly by Alstom and Hitachi.

He concluded that train building in Derby was at ‘serious risk’, and that ‘clarity about future orders, including on HS2’ was needed urgently, warning that if Litchurch Lane closes Britain could need to import trains in future from as far away as China.

The leader of Derby City Council Baggy Shanker was among the protestors in Westminster.

He has already criticised the lack of government involvement, saying: ‘The hundreds of jobs that will disappear at Alstom will be mirrored by thousands more in the supply chain and when the nation does want to order new trains in the future, it will struggle to find anyone in the UK to build them.

‘This is simply unthinkable for a country which gave railways to the world, and the Government has to find the political will to resolve this crisis.’