Japan's longest-serving prime minister, Shinzo Abe, was set to resign, national broadcaster NHK said on Friday, saying he wasnted to avert problems for the government from a worsening health condition.
Abe has battled the chronic disease ulcerative colitis for years. If Abe resigned, he would probably stay on until formally replaced, which requires the ruling Liberal Democratic Party (LDP) to pick a new leader to be formally elected in parliament.
Here are details of some likely contenders to take the helm of the world's third-largest economy.
Finance minister Aso, 79, who also doubles as deputy prime minister, has been a core member of Abe's administration. Without a clear consensus on who should succeed Abe, LDP lawmakers could elect Aso as a temporary leader if Abe resigns.
In 2008, Aso was elected LDP leader and hence, premier, in hopes that he could revive the long-dominant party's fortunes. Instead, the LDP was ousted in a historic election defeat in 2009, languishing in the opposition for the next three years.
The grandson of a former premier, Aso mixes policy experience with a fondness for manga comics and a tendency towards gaffes.
A hawkish former defence minister and rare LDP critic of Abe, Ishiba, 63, regularly tops surveys of lawmakers whom voters want to see as the next premier, but is less popular with the party's lawmakers.
The soft-spoken security maven has also held portfolios for agriculture and reviving local economies.
He defeated Abe in the first round of a party presidential election in 2012, thanks to strong grassroots support, but lost in the second round when only MPs could vote. Then, in a 2018 party leadership poll, Ishiba lost heavily to Abe.
He has criticised the Bank of Japan's ultra-low interest rates for hurting regional banks and called for higher public works spending to remedy growing inequality.
Kishida, 63, served as foreign minister under Abe from 2012 to 2017, but diplomacy remained mainly in the prime minister's grip.
The low-key lawmaker from Hiroshima has been widely seen as Abe's preferred successor but ranks low in voter surveys.
Kishida hails from one of the party's more dovish factions and is seen as less keen on revising the post-war constitution's pacifist Article 9 than Abe, for whom it is a cherished goal.
The BOJ's hyper-easy monetary policy "cannot go on forever," Kishida has said.
Defence Minister Taro Kono, 56, has a reputation as a maverick but has toed the line on key Abe policies, including a stern stance in a feud with South Korea over wartime history.
Educated at Georgetown University and a fluent English speaker, he previously served as foreign minister and minister for administrative reform.
He has differentiated his conservative stances from those of his father, former chief cabinet secretary Yohei Kono, who authored a landmark 1993 apology to "comfort women", a euphemism for women forced to work in Japan's wartime military brothels.
Suga, 71, a self-made politician and loyal lieutenant since Abe's troubled term as premier in 2006 and 2007, was among a band of allies who pushed Abe to run again for the top post in 2012.
Back in office, Abe tapped Suga as chief cabinet secretary, acting as top government spokesman, coordinating policies and keeping bureaucrats in line.
Talk of Suga as a contender bubbled up in April 2019 after he unveiled the new imperial era name, "Reiwa", for use on Japanese calendars after the enthronement of the new emperor.
Suga's clout was dented somewhat by scandals that toppled two cabinet ministers close to him last October.
The name of Koizumi, 39, now environment minister and the son of charismatic former premier Junichiro Koizumi, is often floated as a future premier, but many consider him too young.
He shares some of Abe's conservative views and has paid his respects at Tokyo's controversial Yasukuni Shrine for war dead.
Koizumi has projected a reforming image on the basis of efforts to cut Japan's backing for coal, the dirtiest fossil fuel, but has typically taken care not to offend party elders.
Katsunobu Kato, Yasutoshi Nishimura
As health minister, Kato, 64, was in the limelight in the early days of Japan's coronavirus outbreak but then Economy Minister Yasutoshi Nishimura, 57, a former trade official, emerged as point person on virus policy.
In 2015, Kato, a father of four, was handed the portfolio for boosting Japan's rock-bottom birth rate, a task that met little success. He is a former official of the finance ministry.
Noda, 59, has made no secret of her desire to become Japan's first female premier. An Abe critic, the former internal affairs minister, who also held the portfolio for women's empowerment, fell short of backing to join the race for party leader in 2018.