According to Reuters, Hashimoto said it was not the central Government's role to look into the substantial payments received by Tokyo 2020 in the lead-up to the Japanese capital landing the hosting rights for the Games at the International Olympic Committee (IOC) Session in 2013.

Reuters revealed in March that Haruyuki Takahashi, a former executive at Japanese marketing agency Dentsu, had been paid more than $8 million (£6 million/€6.7 million) by the Bid Committee for undisclosed work, which included lobbying senior IOC members to help Tokyo's successful bid.

Takahashi, now a member of the Tokyo 2020 Organising Committee Board, was reportedly the single largest recipient of money from the Committee.

He admitted to Reuters that he had given disgraced former International Association of Athletics Federations President Lamine Diack and other IOC members gifts as part of an attempt to secure their votes.

The Tokyo 2020 Executive Committee member denied wrongdoing and claimed there was nothing improper with how he used the money.

IOC President Thomas Bach claimed during a recent visit to Tokyo that the payments to Takahashi did not break any IOC rules.

Other payments to and from the Tokyo 2020 Bid Committee remain the subject of controversy.

Lamine Diack and son Papa Massata Diack are at the centre of a corruption probe relating to the bid process for the 2020 Olympics and Paralympics.

They are under investigation in France regarding alleged corruption over payments worth around $2 million (£1.6 million/€1.8 million) made to Black Tidings, a group with ties to Papa Massata.

Both have already been convicted of corruption linked to the Russian doping scandal.

Former Japanese Olympic Committee (JOC) President Tsunekazu Takeda, chair of the Tokyo 2020 Bid Committee, is also being investigated over allegedly authorising the payments to Black Tidings.

Takeda, who denies wrongdoing, resigned as JOC President and as a member of the IOC last year after he was implicated in the scandal.