Japanese Prime Minister Fumio Kishida reiterated Thursday that a state funeral for former leader Shinzo Abe is "appropriate" given his achievements as the country's longest-serving premier, with the approval ratings for the Cabinet sliding due largely to the issue.

As opposition to the slain former leader's state funeral is mounting at home with a significant focus on his suspicious ties with a contentious religious group, Kishida appeared in a parliamentary session to debate the Sept. 27 event for Abe.

To offer condolences across the nation, the government "needs" to hold the funeral as a "state event," Kishida said. A lone gunman fatally shot Abe during an election campaign speech in early July.

Kishida said the government had decided to hold the ceremony to express appreciation for Abe, considering the condolence messages totaling around 1,700 received from more than 260 countries and regions.

He also said U.S. Vice President Kamala Harris, Indian Prime Minister Narendra Modi, Canadian Prime Minister Justin Trudeau, Australian Prime Minister Anthony Albanese and European Council President Charles Michel are among the high-ranking foreign dignitaries expected to travel to Japan for the state funeral.

Kishida's intention to hold the state funeral has been questioned, with Abe's divisive political stances and a series of scandals linked to him cited in addition to the massive amount of taxpayers' money to be used for the event.

Some opposition parties have lambasted Abe's nationalistic views on history and security, with the Japanese Communist Party saying it will boycott the state funeral, which it claims is unconstitutional.

In the Diet session, Kenta Izumi, who heads the main opposition Constitutional Democratic Party of Japan, criticized Kishida's decision to "forcefully" hold the event without consulting with the parliament while giving special treatment to Abe.

Izumi pointed out that there is no legal basis to hold a state funeral for a former prime minister in Japan, but Kishida said the government could do so if the Cabinet adopts a resolution, emphasizing he is not planning to make new rules about such a state funeral.

"Evaluations of a prime minister vary depending on the international and domestic situation," Kishida said, adding it is "desirable for a then government to judge whether to hold a state funeral for a former prime minister."

Prime Minister Fumio Kishida (C) speaks in a parliamentary session in the Diet on Sept. 8, 2022. (Kyodo)

Abe's state-sponsored ceremony will become the second for a former prime minister in the post-war period following one for Shigeru Yoshida, who signed the 1952 San Francisco Peace Treaty that allowed Japan to regain its sovereignty.

With calls growing for Kishida to explain the rationale for holding the state funeral, with an estimated price tag of more than 1.6 billion yen ($11 million) for security and welcoming foreign guests, the prime minister decided to attend the Diet session.

During the session, Kishida also touched on ties between members of his ruling Liberal Democratic Party and a controversial religious group that has come under the spotlight since Abe's shooting.

Kishida has urged his party lawmakers to sever relations with the Unification Church, notorious for its "spiritual sales" in which people are coerced into buying jars and other items for exorbitant prices.

However, the premier denied ordering the group to disband, stressing that the government has already implemented measures, including setting up a consultation center for its victims. He pledged to continue taking necessary steps under the current legal system.

Abe was targeted owing to his perceived links to the church, now officially called the Family Federation for World Peace and Unification. The assailant has told investigators that his mother's substantial donations to the group ruined his family's finances.

Kishida has called for all-out efforts to investigate ties between LDP lawmakers and the Unification Church, founded by a staunch anti-communist and known for its mass weddings.

After Kishida reshuffled his Cabinet and party executive lineups in August, it was revealed that many of those involved had some ties to the Unification Church.

The revelations added to the evidence of a densely intertwined network of contacts between LDP lawmakers and the Unification Church, established in South Korea in 1954 by the late Sun Myung Moon and labeled a cult by critics.

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