Waterloo Station is one of the busiest in the country

The idea has been proposed to ease congestion into Waterloo station between 0800 and 0900 on weekdays.

Network Rail said passengers on the South West mainline into London had to be given an incentive to travel in the hour before or after that peak period.

Other options suggested included running more trains or longer trains.

Network Rail said the amount of miles travelled by passengers using south-west England services into London will increase 20% over the next decade.

Overcrowding problem

At present 75,000 people travel into Waterloo between 0700 and 1000 on weekdays.

A total of 56 trains arrive at the south London station from 0800 to 0900, with very little room for more services in that hour.

Network Rail chief executive John Armitt said: "One option could be to lower the cost for passengers travelling early, although this would be a matter for the Department for Transport and train operating companies."

More trains could be run between 0700 to 0800 and 0900 to 1000 to make the idea more viable.

Services on the Waterloo to Exeter line could be doubled

The organisation's head of group planning Richard Eccles warned that if Waterloo's overcrowding problem was not sorted out trains might have to be held at signals and restricted from entering the station.

Other proposals put forward include increasing platform lengths and using the international Eurostar station for domestic use - after Eurostar's main terminal moves to St Pancras in 2007.

Platforms could be remodelled at nearby Clapham Junction to increase capacity in the area, while a flyover or underpass could be created at Woking in Surrey to ease congestion.

Services could be doubled on the Waterloo to Exeter line, to run hourly.