The company, which owns and operates the entire rail infrastructure, admitted health and safety breaches relating to the accident in October 1999 at Ladbroke Grove.

Thirty-one people died and 400 were injured when a high-speed intercity train crashed into a local service in West London during the morning rush hour.

Network Rail Infrastructure admitted at least 16 infringements at Blackfriars Crown Court, in London. Relatives of three of the victims attended the 20-minute hearing.

The charge referred to inadequate signal sighting distances and the obscuring of part of a signal.

Other parts of the charge mean that the company has admitted that it failed to ensure the convening of a signal- sighting committee after equipment was installed in 1995, and also after six incidents when signals were passed when red between 1996 and 1998. In addition, it did not carry out “adequate risk assessments” or investigations following them.

The guilty plea is only an admission of risk creation and does not mean that the company accepts responsibility for the deaths and injuries.

Sentencing was adjourned until December 18 to give the defence time to examine a mass of unused material.

Linda Di Lieto, whose son Sam, 24, was killed, said: “It seems it is just a game to them. How many times can they keep delaying? This has been going on for seven years.”

A spokesman for Network Rail said: “Lessons have been learnt and the rail industry has changed enormously for the better. The tragedy happened before the Train Protection and Warning System (TPWS) became available. TPWS automatically applies a train’s brakes if it is approaching a red signal too quickly to stop. This system has greatly reduced the risk of an accident caused by a train passing a red light.”

Louise Christian, a solicitor who acted for the families, said: “Two weeks ago bereaved families were given assurances that they [Network Rail] were being prosecuted on the basis that their health and safety breaches caused the 31 deaths, and I hope those assurances are being maintained.

“The problem is they have pleaded guilty in a forum where there can be no proper accountability because the only penalty is a fine against a company heavily subsidised by the taxpayer. The sad thing is that Ladbroke Grove could happen tomorrow because the crucial recommendations of Lord Cullen on train protection systems were not implemented by the Government.”

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