The planned extension of the Hokkaido Shinkansen to Sapporo will be delayed until after fiscal 2030, informed sources have said.

The Japan Railway Construction, Transport and Technology Agency, or JRTT, has decided to abandon the plan to open the extended section by the end of fiscal 2030, the sources said Wednesday.

A decision is expected to be announced in early May, after the Golden Week holiday period.

According to the sources, tunnel construction for the section has proven challenging, forcing JRTT to accept a delay. The agency will seek to set a new schedule for the opening.

The Hokkaido Shinkansen section between Shin-Aomori and Shin-Hakodate-Hokuto was opened in March 2016. The section between Shin-Hakodate-Hokuto and Sapporo was originally scheduled to open in fiscal 2035, but the Japanese government and ruling parties agreed in 2015 to advance the extension to fiscal 2030.

With tunnels accounting for about 80% of the extended section, huge rocks and poor geological conditions have hampered construction.

In December 2022, an expert panel under the transport ministry reported that the extension work was seeing a delay of around three to four years. It also estimated that the cost of the extension would reach around ¥2.3 trillion, about ¥645 billion higher than initially expected.

The delay in the opening of the new section is likely to affect local governments that have been considering urban development and other issues on the assumption that the new section would be in operation from fiscal 2030.

Hokkaido Railway, or JR Hokkaido, is also worried that the delay could make it difficult to predict the positive effects of the extended section on its business condition.