The Ministry of Finance plans to build a new government complex after the existing one on Chaeng Watthana Road is fully occupied, said permanent secretary Areepong Bhoocha-oom.
Mr Areepong said the new government services centre should be built along the route of the new Red Line mass transit route.
He said the complex would cover a large area that would be no less than the existing government complex.
Mr Areepong has an idea to develop the project with a concept of greenery, including a plan to develop a big garden inside the building.
"We have selected some locations that I cannot tell you about right now, but it would be built in an area along the electric train line from Taling Chan to Bang Sue and from Bang Sue to Rangsit," said Mr Areepong.
The existing government complex was completed in 2008 after construction began in 2005 with an investment of 20 billion baht.
It was the first project for which funds were raised through a securitisation method.
The complex covers nearly 400 rai of land on Chaeng Watthana Road and has useable space of 929,000 square metres.
The new project is essential because many government agencies in central Bangkok should be relocated to the outskirts, said Mr Areepong.
The Interior Ministry and Defence Ministry in the old town at Rattanakosin Island are surrounded by high-density offices and residential areas, causing severe traffic congestion.
Under the government's plan, the old buildings that have been used as offices of government agencies in this area should be renovated as tourist destinations as well as a cultural centre.
"The interior and defence offices may be adjusted to become a museum similar to the Smithsonian that was initiated by Prime Minister Yingluck Shinawatra," said Mr Areepong.
Furthermore, he suggested that the government may consider building a knowledge centre for children and the public on a large plot of state-owned land near the Thailand Cultural Centre and Rama IX and on land belonging to the State Railway of Thailand (SRT).
A land plot near Chatuchak weekend market, also owned by the SRT, may be developed to be the country's first distribution centre for the One Tambon One Product scheme.
The policy to develop state-owned land was initiated by the government in order to improve the logistics and transport systems as well as to improve the appearance of Bangkok.