Tokyo  - Japan's benchmark Nikkei 225 Stock Average fell to a four-month low Tuesday after Finance Minister Shoichi Nakagawa said he would step down following accusations he was drunk at a Group of Seven press conference.

The Nikkei closed at 7,645.51, down 104.66 points, or 1.35 per cent, and the broader Topix index of all first section issues was also down 13.57 points, or 1.76 per cent, at 756.53.

Nakagawa apologized "for the significant trouble I caused" although he denied he was drunk after slurring his words and appearing drowsy at the weekend press conference in Rome held during a meeting of the finance ministers of seven of the world's largest economies. He blamed cold medication and jet lag.

His resignation represented a blow to Prime Minister Taro Aso's government, which has seen its popularity plummet and criticism rise for its handling of the economic crisis as elections for the lower house of the Diet loom at the latest by September.

On currency markets at midday (0300 GMT), the dollar traded at 92.41-46 yen, up from late Monday's quote of 91.56-58 yen.

The euro was quoted at 1.2654-59 dollars, down from Monday's 5 pm quote of 1.2749-51 dollars, and at 116.97-117.02 yen, up from 116.73-77 yen. (dpa)