Rail bosses have faced strong criticism over their actions in the run up to the Ladbroke Grove crash.

Lord Cullen, who has conducted a painstaking investigation into the crash which killed 31 people, found that the rail managers had repeatedly ignored warnings that drivers were having problems reading signals on the line into London's Paddington station.

He said that the accident had been caused by "lamentable institutional paralysis".

His report also criticises Railtrack for its management of the section of track in west London where a Thames train collided with a Great Western express train. It says that little was done to make signals more visible to drivers.

Welcoming the report, the transport secretary. Stephen Byers, said Railtrack must act upon its recommendations.

"On such a day our thoughts turn to the survivors and bereaved of that tragic accident. We cannot begin to imagine the pain and suffering felt by these people and it is important that we bear their experiences in mind as we act to improve rail safety in this country," he began.

"Safety is paramount and at the very heart of our policies on revitalising the railways. Our railways are safe, but we must never be complacent. Safety is a matter of continual improvement and I have asked the HSC to ensure that the recommendations are acted upon, and to report to me within six months. I now await the final part of Lord Cullen's report into the culture, management and regulation of safety on the railways. This will be a particularly valuable document which will enable us to take the further necessary measures to enhance rail safety," he said.

Cullen has drawn up 89 recommendations to avoid a repeat of the fatal accident. He accepted that the industry had made some improvements saying that since Ladbroke "the world has not stood still".

A spokesman for the Health and Safety Executive said: "We believe that the railways can be made safer."

Railtrack and train operating bosses have claimed that improvements have already been made following the accident.

Terry Worral of Thames Trains said Cullen had issued "a very fair and balanced judgement". He said: "Clearly, this report is a major challenge for the industry."

But rail unions have questioned whether any improvements have been made. Mick Rix, Aslef's general secretary, said: "There are still too many locations where there are badly-sited signals. Obviously, we need to see rapid improvements to ensure incidents caused by badly-sited signals do not lead to future tragedies."

A second report into overall report safety will be published by Lord Cullen at a later date.