Hua Lamphong railway station is scheduled to make its final call for passengers late next month.

The State Railway of Thailand (SRT) will eventually have to stop station operations to allow for commercial development of the site's land, Transport Minister Saksayam Chidchob said on Monday.

Such development is expected to bring in 800 billion baht over 30 years, which the SRT needs considering it is currently about 600 billion baht in the red, he said before a meeting with SRT on the matter.

Hua Lamphong station, which has served as the city's main rail hub for 105 years, is scheduled for decommissioning in late December.

An SRT source said rail services at Hua Lamphong will cease on Dec 23. The plan sparked outrage as Bang Sue Grand Station, which will function as Bangkok's main rail hub from then onwards, isn't as well connected to Bangkok's inner-city areas.

"Keeping Hua Lamphong open will result in skyrocketing costs. I'm not afraid to make the decision, no matter who says what," said Mr Saksayam.

Ahead of the closure, passenger service numbers to and from Hua Lamphong will decrease from 118 to 22 a day. Cargo services will be diverted to Chiang Rak Noi station in Ayutthaya, he said.

"The plan to close Hua Lamphong will be implemented step-by-step, not abruptly," he said, adding he has also asked SRT to carefully review its train service operation plan at Hua Lamphong to minimise disruptions. "The final decision will be reached later and opinions from all sides will be taken into consideration."

When asked about the lack of convenient connection between Hua Lamphong and Bang Sue stations, Mr Saksayam said public transport operators, including Bangkok Mass Transit Authority, will be asked to add services between the stations.