Services are still not back to normal following Hatfield

Mr Winsor said it was clear he needed to "concentrate the minds" of Railtrack after the rail operator said at least 16 passengers lines would not be ready by the May date.

He warned Railtrack that it could face legal action from the train operating companies if they do not meet that deadline.

Mr Winsor said Railtrack had already missed three self-imposed deadlines for bringing the network back to normal - at Christmas, early in the New Year and the latest one at Easter.

He told BBC Radio 4's Today programme: "I expect the company to comply with this. It is a breach of their statutory duty if they fail to comply and there can be legal consequences on the part of the train operating companies if that happens.

Railtrack's asset

"I'm not looking in terms of failure. I'm looking in terms of success. I believe the company can do it and they will do it."

The company did not have adequate knowledge of the condition and capacity of its assets

Rail regulator Tom Winsor

He also called for the publication of the register of Railtrack's assets, and was severely critical of the company's knowledge of Britain's track network at the time of the Hatfield crash.

"The Hatfield accident demonstrated that the company did not have adequate knowledge of the condition and capacity of its assets, despite the fact that Railtrack was in existence for seven years and had been privatised for five year."

If the company had known the state of the network, it would not have had to impose 1,000 speed restrictions and emergency timetables which followed the Hatfield crash in October, Mr Winsor added.

'Patience wearing thin'

Anthony Smith, national director of the Rail Passengers' Council, said: "Passengers' patience in parts of the country is now wearing very thin.

"The inability of train companies to tell their passengers when disruption will end is becoming increasingly frustrating."

He said the setting and then breaking of successive deadlines for the end of this work was leading to "disillusionment".

"Railtrack and train companies must be realistic with passengers and tell them the truth about when services will return to pre-Hatfield levels," he said.