Trains started running again this morning (Fri 4 Jan) on the West Coast main line after major engineering work over Christmas at Rugby over-ran by four days.

"I know we've let passengers down," said Network Rail chief executive Iain Coucher. "An investigation into the causes of the over-run has been launched and I will be chairing a high-level meeting next week to review what's happened.

"I will be summoning our project managers, Bechtel, and the principal contractors involved to attend so they can personally explain to me what has gone wrong.

"They gave me assurances before Christmas on which they have not delivered. I want answers from them."

Work at Rugby over the Christmas period included installing more than 5km of overhead line; bringing into use 5.3km of new track, 15 new sets of points and 18 new signals; making 16 new track connections, and installing nine new signalling 'booster' cabinets.