Rail regulator Tom Winsor has told Stephen Byers, the transport secretary, that Railtrack's senior managers are a barrier to improvements in the industry.

The lack of engineering and railway experience in the infrastructure company's top three layers of management were cited by the rail watchdog as a cause for concern.

Former Railtrack chief, Gerald Corbett, is to leave his new job with retailer Kingfisher for a life of "obscurity" following continuing controversy over his pay-off and his role in the Hatfield and Paddington rail crashes.