US Secretary of State Antony Blinken, third left, speaks after a meeting with Japan s Prime Minister Fumio Kishida at the prime minister s official residence Monday, July 11, 2022, in Tokyo. Blinken pays a brief condolence visit to Japan following the assassination of former Japanese Prime Minister Shinzo Abe. AP
Japan's ruling coalition meanwhile declared victory in a sombre election held Sunday, just two days after Abe was gunned down on the campaign trail.
Abe's body was moved from his family home to the Zojoji temple on Monday afternoon, where his wake is being held ahead of tomorrow's private funeral.
Public memorials for him are expected at a later date, with no immediate plans set for the events.
Earlier, US Secretary of State Antony Blinken made a previously unscheduled trip to Japan while travelling in Asia to offer Washington's condolences.
He handed Prime Minister Fumio Kishida letters from US President Joe Biden for Abe's family and said he had come because "we're friends, and when one friend is hurting, the other friend shows up".
Abe "did more than anyone to elevate the relationship between the United States and Japan", Blinken added, calling him "a man of vision with the ability to realise that vision".
US Treasury Secretary Janet Yellen, in Tokyo for meetings ahead of a gathering of G20 finance chiefs in Bali, also attended the wake, as did ambassador Rahm Emanuel, according to a Treasury official.
The man accused of Abe's murder, 41-year-old Tetsuya Yamagami, is in custody and has told police he targeted the former leader because he believed he was linked to a specific organisation that authorities have not yet named.
Japanese media reports said he blamed the group, described as a religious organisation, for his family's financial troubles because his mother made large donations to it.
The Unification Church, a global religious movement founded in Korea in the 1950s, said on Monday that Yamagami's mother was a member.
"She has been attending our events about once a month," Tomihiro Tanaka, president of the church in Japan, told a hastily organised press conference in Tokyo, declining to comment on donations she may have made.
Tanaka said the church was horrified by Abe's "barbaric" murder and would cooperate with police investigations.
Yamagami, believed to have spent three years in Japan's navy, had watched YouTube videos to help learn how to build homemade guns like the one used in the attack, investigative sources told local media.
Sunday's election went ahead despite the assassination, with Kishida saying it was important to show violence would not defeat democracy.
Abe's long-ruling Liberal Democratic Party and its coalition partner Komeito won 76 of the 125 upper house seats up for grabs, up from the 69 seats they previously held, according to national news outlets.
The victory had been widely expected even before the assassination.
Both parties belong to what is now a two-thirds supermajority open to amending the country's pacifist constitution. Abe long sought to reform the charter to recognise the country's military.
Kishida told reporters on Monday that the seats gained represented a chance to "protect Japan" and build on the achievements of Abe, who local media said Monday would receive Japan's highest decoration.
Kishida, who took office in September, has pledged to tackle the pandemic, inflation and issues related to Russia's invasion of Ukraine, and there was speculation that Friday's attack could bolster his support.
But turnout was up only marginally, and still low at a reported 52 percent.
A record 35 female candidates were elected, and some fringe candidates also won for the first time, including one from an anti-vaccination party.
Abe was the scion of a political family and became the country's youngest post-war prime minister when he took power for the first time in 2006, aged 52.
His hawkish, nationalist views were divisive, particularly his desire to reform the pacifist constitution, and he weathered a series of scandals, including allegations of cronyism.
But he was lauded by others for his economic strategy, dubbed "Abenomics", and his efforts to put Japan firmly on the world stage, including by cultivating close ties with Biden's predecessor Donald Trump.