Prime Minister Fumio Kishida accepted the resignation of a third scandal-tainted Cabinet minister and ally Sunday night in a fresh blow to his administration that comes just as he returns to Japan after attending three key regional summits.

Internal affairs minister Minoru Terada, a key Kishida ally and member of his faction, turned in his resignation following a string of funding-related scandals that called his credibility into question. Terada’s exit is likely to further damage Kishida’s public approval ratings and raise doubts about the prime minister’s leadership ability as well as questions about his political future, including from members of his own party.

Kishida apologized for having yet another Cabinet member exit during the current Diet session due to a scandal.