Network Rail has admitted that not enough trains are running on time as it faces a reported record £70 million fine for poor punctuality.

The Sunday Telegraph reported that it will tell the Office of Rail Regulation tomorrow 89.9% of trains arrived at their destinations on time.

The benchmark target for Network Rail is 92.5% and ORR fines it for every 0.1% it misses by, leaving it facing a fine of around £70 million.

Network Rail said excessive congestion and bad weather had offset improvements made to rail infrastructure.

A spokeswoman said:"Passengers are not currently experiencing the very high levels of train punctuality we had promised.

"While we have been successful in making our infrastructure more reliable, it hasn't been enough to offset the difficulties caused by excessive congestion or bouts of extreme weather.

"Missing our regulatory targets for punctuality is disappointing and our focus for the coming five year period is to restore record levels of performance and spend and invest some £38 billion in our railways targeting the busiest parts of our network to relieve congestion and provide more trains, more seats and quicker, greener journeys."

In February NR agreed to the ORR's plan for the network over the next five years, which would aim to improve punctuality.

It will also aim to bring down the costs of running the railways by 20% for the five-year period starting in April.

NR will have to meet a target of running 90% of trains on time on London, south east England, regional and Scottish services and improving reliability on long-distance trains.

The company is also signing up to improved standards of infrastructure management, network resilience, and safety for passengers and railway workers.

Last November ORR said NR has underspent on maintenance work, deferred plans to renew infrastructure and let engineering work overrun at times.

It said more than half of the the delays on the network were caused by problems attributable to NR, which was facing a possible fine "in excess of £80 million" if long-distance train punctuality did not improve.

An ORR spokeswoman declined to comment on today's reports.

A spokesman for Passenger Focus said: "The £38bn investment for Network Rail over the next five years is welcome, particularly during difficult economic times.

"Passengers should ultimately see an improved rail service bringing the things they tell us they want: improved punctuality, reliable trains with more seats. Punctuality should be a particular focus given the priority passengers give to it."