TOKYO - Japan's government announced Friday the replacement of a senior official and close aide to Prime Minister Sanae Takaichi, in a de facto dismissal following a reported extramarital affair that involved state-funded business trips.

Tadashi Mogi, a secretary to Chief Cabinet Secretary Minoru Kihara on secondment from the Ministry of Economy, Trade and Industry, will be replaced by Keisuke Sasaki, director general for policy planning and coordination in the ministry, on Tuesday, according to the government.

Earlier this month, a monthly magazine reported that while working as an industry ministry official, Mogi repeatedly invited a woman to hotels in Osaka where he was staying at public expense during trips related to last year's World Expo in the western Japan city.

At a press conference, Kihara, the top government spokesman, refrained from explaining the reason for "a specific personnel change" but said the ministry's investigation into Mogi was ongoing.

Mogi worked under Takaichi when she was a senior vice minister at the ministry.

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