The Highways Agency (HA), which aims to spend more than £1.5bn on road improvements in the next two years, is urging its staff to leave their cars at home and take the train to work instead.
The executive agency of the Department for Transport is offering all 640 employees in its Birmingham office a 50% discount on rail season tickets. A total of 70 have taken up the offer so far.
Steve Williams, HR director at the HA, which has promised to spend £589m on major road improvements in 2005/06, and £972m in 2006/07, said: "We wish to reduce the amount of waste materials from our offices - such as paper and office products. We also wish to support the environment alongside our roads."
It is estimated that UK businesses lose at least 15bn a year because of the country's poor transport infrastructure.
Nearly 40% of the 2,000 companies questioned by the British Chambers of Commerce last year said that their potential for growth was limited by the UK's transport infrastructure, while three-quarters said that operating costs were increased by delays.