Japanese Foreign Minister Hayashi Yoshimasa will not attend a meeting of his counterparts from the Group of 20 nations in India due to Diet deliberations.
The G20 foreign ministers' conference will be held for two days starting Wednesday in New Delhi.
Scheduled participants include US Secretary of State Antony Blinken, Russian Foreign Minister Sergey Lavrov and Chinese Foreign Minister Qin Gang.
Japan's Foreign Ministry announced on Wednesday that State Minister for Foreign Affairs Yamada Kenji will sit in for Hayashi at the meeting.
All members of Prime Minister Kishida Fumio's Cabinet must take part in the Upper House Budget Committee's question and answer sessions through Thursday.
Some Japanese government officials and members of the ruling bloc have supported Hayashi's decision, citing the importance of budget deliberations in the Diet.
But others call it a diplomatic setback for Japan, which holds this year's Group of Seven presidency.
Hayashi does plan to attend a meeting of Quad foreign ministers to be held on the sidelines of the G20.
The Quad framework consists of Japan, the US, Australia and India.