The education and sports ministry is working on slashing the cost of replacing National Stadium for the 2020 Tokyo Olympics and projected facilities surrounding it to ¥180 billion, sources said Friday.

The ministry had originally calculated the project's cost at as much as ¥300 billion. The main structure of the stadium is now expected to cost ¥150 billion, rather than the initial figure of ¥130 billion, but accompanying costs are to be reduced.

The ministry wants to simplify various aspects of work on the stadium and try to reduce costs on building materials. It will stick with the basic concept, including a retractable roof.