TOKYO -- Citing arm injury, Japanese Prime Minister Sanae Takaichi on Sunday canceled at the last minute her planned appearance on a live party leaders' debate aired by public broadcaster NHK, drawing widespread criticism from opposition parties.

Norihisa Tamura, executive acting chairperson for Policy Research Council of the Liberal Democratic Party (LDP), replaced Takaichi and appeared on the program. He said that Takaichi likely strained her arm through repeated handshakes and constant movement on the campaign trail, making her unable to appear on the show.

Opposition lawmakers voiced dissatisfaction over the sudden cancellation. Tomoko Tamura, chair of the Japanese Communist Party, wrote on social media that she was informed of Takaichi's absence only about 30 minutes before the program began, adding that the broadcaster had briefly "fallen into chaos."

With opportunities for party leaders to debate publicly already limited during the election period, she questioned how voters could be expected to place their trust in a candidate who "does not even show up for discussions."

Akiko Oishi, co-president of Reiwa Shinsengumi, also criticized the move, noting that recent Japanese media reports alleged that groups linked to the Family Federation for World Peace and Unification, formerly known as the Unification Church, had provided funds to an LDP branch associated with Takaichi through the purchase of political fundraising party tickets.

Oishi said she had planned to question Takaichi directly on the matter during the program but was unable to do so due to her absence, and called on the prime minister to "offer an explanation to the public before voting day."

In another party leaders' debate held recently, some Japanese media outlets observed that Takaichi appeared visibly displeased when Oishi raised questions about her alleged ties to the Unification Church, footage of which later sparked online discussion.