Stephen Byers has hit back at critics of the government's handling of Railtrack.

The transport secretary told MPs that a "so-called leaked" document of rules about Railtrack's future had been laid before parliament on October 8 and a copy placed in the Commons library.

In an emergency question in the Commons, shadow transport secretary Theresa May had argued that Byers' handling of the Railtrack administration had called into question the credibility of the whole government and she demanded a full public independent inquiry.

The transport department's decision to set up two railway strategy directorates has also raised fears that the government is renationalising the industry by the back door.