The Government is being urged to reverse the "disastrous" decision to award a lucrative rail contract to German giant Siemens, which has led to the loss of 1,400 jobs at a rival firm.

Derby-based Bombardier - which also has an aerospace arm, based in Belfast - is cutting 1,400 jobs after failing to win the £1.4bn contract to build new carriages for the Thameslink route between Bedford and Brighton.

Union leaders were today meeting Transport Secretary Philip Hammond to ask him to help reverse the decision.

Unite assistant general secretary Diana Holland said: "The weight of public opinion is on the side of Bombardier and against the Government's short-sighted decision.

"Politicians, the public and the media are equally shocked by the Government's decision not to award Bombardier the Thameslink contract.

"The Government must re-think its disastrous decision and support British manufacturing and skilled jobs."

The Rail Maritime and Transport union presented the minister with a dossier on the history of Siemens activities and will call for an investigation into whether the company is "fit and proper".

General secretary Bob Crow said: "Not only have we demolished the Government's claim that Siemens represented the best value for the British taxpayer by exposing the fact that the wider economic impact of running down Bombardier was never taken into account but we now have some serious questions that need answering about the business practices of Siemens.

"We are calling on Phillip Hammond to call off the jobs massacre at Bombardier, and the destruction of the UK train building industry, and to take full account of the barrage of new evidence that has been uncovered since this process began. The fight to save train building in the nation that gave the railways to the world remains well and truly on."

The RMT has warned that thousands of jobs are at stake in the East Midlands because of the cuts at Bombardier, although Siemens has pointed out that its contract will lead to the creation of new jobs across the UK.

Meanwhile, a survey of 2,700 adults by YouGov showed that almost three in five believed that the Government should prioritise British companies over foreign ones when awarding contracts.