Mrs Soithip said if approved the new department that would take shape in a year.
It would supervise railway services and maintenance and the projects of the State Railway of Thailand (SRT) and the Mass Rapid Transit Authority, and would also handle state railway investment projects.
The workforce of the new department could come from staff at the SRT, the Office of Transport and Traffic Policy and Planning, the Department of Highways and the Department of Rural Roads, she said. These agencies are all under the Ministry of Transport.
Mrs Soithip also said that Thailand, Cambodia, Laos, Vietnam, China and Myanmar planned to completely connect their railways by 2020.