Network Rail, the heavily-indebted body that runs Britain's tracks and most prominent train stations, has warned that even their best contractors face suspension if safety records do not get better.
The threat comes after a rail worker, 26-year-old Scott Dobson, was hit and killed by a Scunthorpe to Lincoln train in December.
Network Rail has privately described this as a "watershed incident" and installed a 10-point plan which it hopes will reform safety standards across its routes.
However, Network Rail's latest published board minutes, which detail a meeting held on 24 April, show the organisation is willing to go further to prevent any further deaths.
The minutes state that Simon Kirby, Network Rail's managing director for infrastructure projects, met the chief executives of the organisation's major contractors at a safety summit. "They had been advised that if safety records did not improve Network Rail could not rule out the need to suspend principal contractors irrespective of economic and performance impact."
The minutes were published after Network Rail revealed last week that its debt mountain had again increased. The Government-backed group now has a net debt of more than £30bn and also missed crucial punctuality targets, which could lead to a fine.
However, its chief executive, Sir David Higgins, who previously oversaw the construction of the London 2012 Olympic Games, is looking to win lucrative advisory work overseas.
In another setback for the rail industry, the hugely controversial, £32.7bn High Speed Two proposal, which will slash journey times from London to Birmingham to 49 minutes, was dealt a blow by campaigners who have been so incensed by the plans.
The Information Commissioner's Office agreed with their demands that it was in the public's interest for the full report into HS2 by the Cabinet Office's Major Project Authority (MPA) to be released immediately.
Last month, the MPA gave HS2 a re-amber rating, which means that there are major concerns about the project. The Cabinet Office now has until next month to publish the report, but can appeal.