NETWORK Rail has apologised to rail travellers because it was to blame for seven out of every 10 delays on the East Coast Mainline over the last month.

The firm apologised to East Coast customers after publishing punctuality figures which showed it was at fault for 70 per cent of delays on the line, which runs between London and Edinburgh through York.

Around one in six East Coast trains were late between August 18 and September 14, making the nationalised network the least punctual in the country during that period. Nationally, Network Rail was to blame for 60 per cent of delayed services, as punctuality on the railways fell 1.7 per cent year on year.

The company said: "Network Rail would like to apologise to East Coast's customers for the disruption caused by these infrastructure failures and the company is redoubling its efforts to improve the reliability of this critical piece of railway infrastructure."

The firm, which is responsible for maintaining tracks, signalling, bridges, tunnels, level crossings, viaducts and 17 stations, said deaths on the line and other external factors made up a fifth of the delays it was to blame for on East Coast services, with the biggest failures being related to overhead wire failures in three separate incidents.

Of the 60 per cent of train delays Network Rail was responsible for nationwide, external factors such as weather, trespass and vandalism, and cable theft were to blame.

A train is deemed to have arrived on time if it arrives within five minutes of its expected time for commuter services and within 10 minutes for long-distance services. The annual average of trains arriving on time now stands at 90.7 per cent.