Andy Street, the Conservative mayoral candidate for Birmingham, has said he is “utterly certain” that the Government will continue to back the HS2 rail scheme, and he has described press speculation that it will be cancelled as “manifesto silly season” stories.

Mr Street added that, “while some back-bench Conservative MPs may be pushing for a rethink, the Government is sticking to its guns”. Construction work on the high-speed line between London and Birmingham is due to get under way later this year.

Asked about it at a Birmingham Mail public debate, Mr Street said: “I am utterly certain that the Government is committed to HS2, and that’s the right decision. It’s about bold leadership.

“There will be many people in the Conservative Party who would say it is a good thing to not go ahead, and I suspect that the manifesto silly season is a wonderful opportunity for them to relaunch their idea.

"However, the Government has been very firm that HS2 will benefit this region, because it makes us the centre of the new transport system that’s going to dominate for the next century.”

About £3 billion has already been spent on HS2, with some predictions that the total cost could exceed £100 billion. HS2 critic and North West Leicestershire MP Andrew Bridgen recently told The Sun newspaper: “The General Election gives us a great opportunity to kill this expensive project.”