His resignation could undermine some of Japan’s planned economic reforms and reduce the chances of Mr Abe calling a general election this summer.

“Politically, this will stabilise the government,” said Masatoshi Honda, a professor of politics at Kinjo University. “If Mr Abe had left him in place then the scandal would have gone on and on in parliament. But economically, Mr Amari was a pillar of Abenomics.”

Within the cabinet, Mr Honda said, “finance minister Taro Aso was on the side of fiscal consolidation and Mr Amari was on the side of growth — together they struck a good balance”.

Without Mr Amari operating from the Cabinet Office, the finance ministry may regain some of its traditional power, pushing for tax increases to lower Japan’s deficit rather than stimulus to boost growth.

Mr Honda said much would depend on who replaces Mr Amari. He pointed to Yoshimasa Hayashi, a political veteran and former agriculture minister, as one option. Mr Hayashi was parachuted into the agriculture ministry last year after a similar scandal, helping to manage opposition to TPP among farmers.